liu.seSearch for publications in DiVA
Change search
Refine search result
12 1 - 50 of 58
CiteExportLink to result list
Permanent link
Cite
Citation style
  • apa
  • harvard1
  • ieee
  • modern-language-association-8th-edition
  • vancouver
  • oxford
  • Other style
More styles
Language
  • de-DE
  • en-GB
  • en-US
  • fi-FI
  • nn-NO
  • nn-NB
  • sv-SE
  • Other locale
More languages
Output format
  • html
  • text
  • asciidoc
  • rtf
Rows per page
  • 5
  • 10
  • 20
  • 50
  • 100
  • 250
Sort
  • Standard (Relevance)
  • Author A-Ö
  • Author Ö-A
  • Title A-Ö
  • Title Ö-A
  • Publication type A-Ö
  • Publication type Ö-A
  • Issued (Oldest first)
  • Issued (Newest first)
  • Created (Oldest first)
  • Created (Newest first)
  • Last updated (Oldest first)
  • Last updated (Newest first)
  • Disputation date (earliest first)
  • Disputation date (latest first)
  • Standard (Relevance)
  • Author A-Ö
  • Author Ö-A
  • Title A-Ö
  • Title Ö-A
  • Publication type A-Ö
  • Publication type Ö-A
  • Issued (Oldest first)
  • Issued (Newest first)
  • Created (Oldest first)
  • Created (Newest first)
  • Last updated (Oldest first)
  • Last updated (Newest first)
  • Disputation date (earliest first)
  • Disputation date (latest first)
Select
The maximal number of hits you can export is 250. When you want to export more records please use the Create feeds function.
  • 1.
    Davidsson, Anette
    et al.
    Östergötlands Läns Landsting, Heart and Medicine Center, Department of Clinical Physiology in Linköping.
    Georgiopoulos, C
    Östergötlands Läns Landsting, Heart and Medicine Center, Department of Clinical Physiology in Linköping.
    Gustafsson, Agnetha
    Linköping University, Department of Medical and Health Sciences, Radiation Physics. Linköping University, Faculty of Health Sciences. Östergötlands Läns Landsting, Center for Surgery, Orthopaedics and Cancer Treatment, Department of Radiation Physics.
    Zachrisson, Helene
    Östergötlands Läns Landsting, Heart and Medicine Center, Department of Clinical Physiology in Linköping.
    Evaluation and comparison of quantification tools for early diagnosis of Parkinson's disease with DaTSCAN SPECT.2011Conference paper (Refereed)
  • 2.
    Davidsson, Anette
    et al.
    Linköping University, Department of Medical and Health Sciences, Division of Cardiovascular Medicine. Linköping University, Faculty of Health Sciences. Östergötlands Läns Landsting, Heart and Medicine Center, Department of Clinical Physiology in Linköping.
    Georgiopoulos, Charalampos
    Linköping University, Center for Medical Image Science and Visualization (CMIV). Linköping University, Department of Medical and Health Sciences, Division of Radiological Sciences. Linköping University, Faculty of Medicine and Health Sciences. Region Östergötland, Center for Diagnostics, Department of Radiology in Linköping.
    Dizdar (Dizdar Segrell), Nil
    Linköping University, Department of Clinical and Experimental Medicine, Division of Neuroscience. Linköping University, Faculty of Health Sciences. Östergötlands Läns Landsting, Local Health Care Services in Central Östergötland, Department of Neurology.
    Granerus, Göran
    Linköping University, Department of Medical and Health Sciences, Division of Cardiovascular Medicine. Linköping University, Faculty of Health Sciences. Östergötlands Läns Landsting, Heart and Medicine Center, Department of Clinical Physiology in Linköping.
    Zachrisson, Helene
    Linköping University, Center for Medical Image Science and Visualization (CMIV). Linköping University, Department of Medical and Health Sciences, Division of Cardiovascular Medicine. Linköping University, Faculty of Health Sciences. Östergötlands Läns Landsting, Heart and Medicine Center, Department of Clinical Physiology in Linköping.
    Comparison between visual assessment of dopaminergic degeneration pattern and semi-quantitative ratio calculations in patients with Parkinsons disease and Atypical Parkinsonian syndromes using DaTSCAN (R) SPECT2014In: Annals of Nuclear Medicine, ISSN 0914-7187, E-ISSN 1864-6433, Vol. 28, no 9, p. 851-859Article in journal (Refereed)
    Abstract [en]

    Objective To verify if I-123-FP-CIT, DaTSCAN (R) can differentiate early stages of Parkinsons disease (PD) as well as patients with Atypical Parkinsonian syndromes (APS) from manifest Parkinsons disease. Methods 128 consecutive patients were investigated with I-123-FP-CIT SPECT during a 4-year period. All patients were diagnosed according to the established consensus criteria for diagnosis of PD (n = 53) and APS (n = 19). Remaining patients were grouped early PD (before onset of L-DOPA medication), (n = 20), vascular PD (n = 6), and non-PD syndromes (n = 30) and SWEDD (n = 1). SPECT images were analyzed visually according to a predefined ranking scale of dopaminergic nerve cell degeneration, distinguishing a posterior-anterior degeneration pattern (egg shape) from a more global and severe degeneration pattern (burst striatum). Striatum uptake ratios were quantitatively analyzed with the 3D software, EXINI. Results In the group of APS patients, the burst striatum pattern was most frequent and found in 61 % (11/18 patients). In PD patients, the egg shape pattern was dominating, especially in early PD where it was present in 95 % (19/20 patients). The positive predictive value for the egg shape pattern to diagnose PD was 92 % in this material (APS and all PD patients) and the specificity 90 % for the burst striatum pattern to exclude APS. The uptake ratios were reduced in both PD and APS patients and closely related to the image ranking. Conclusion In this study, we found that in more than half of the patients it was possible to differentiate between PD and APS by visual interpretation only. Similar results were obtained using semi-quantitative uptake ratios. Combining visual assessment with uptake ratios did not add to the discriminating power of DaTSCAN (R) SPECT in this material.

  • 3.
    Davidsson, Anette
    et al.
    Linköping University, Department of Medical and Health Sciences, Division of Cardiovascular Medicine. Linköping University, Faculty of Health Sciences. Östergötlands Läns Landsting, Heart and Medicine Center, Department of Clinical Physiology in Linköping.
    Georgiopoulos, Charalampos
    Linköping University, Center for Medical Image Science and Visualization (CMIV). Linköping University, Department of Medical and Health Sciences, Division of Radiological Sciences. Linköping University, Faculty of Medicine and Health Sciences. Region Östergötland, Center for Diagnostics, Department of Radiology in Linköping.
    Dizdar Segrell, Nil
    Linköping University, Department of Clinical and Experimental Medicine, Division of Neuroscience. Linköping University, Faculty of Health Sciences. Östergötlands Läns Landsting, Local Health Care Services in Central Östergötland, Department of Neurology.
    Granerus, Göran
    Linköping University, Department of Medical and Health Sciences, Division of Cardiovascular Medicine. Linköping University, Faculty of Health Sciences. Östergötlands Läns Landsting, Heart and Medicine Center, Department of Clinical Physiology in Linköping.
    Zachrisson, Helene
    Linköping University, Center for Medical Image Science and Visualization (CMIV). Linköping University, Department of Medical and Health Sciences, Division of Cardiovascular Medicine. Linköping University, Faculty of Health Sciences. Östergötlands Läns Landsting, Heart and Medicine Center, Department of Clinical Physiology in Linköping.
    Comparison between visual assessment of dopaminergic degeneration pattern and semi-quantitative ratio calculations in patients with Parkinson's disease and Atypical Parkinsonian snydromes using DaTSCAN SPECT2014Conference paper (Other academic)
    Abstract [en]

    Background: Parkinson's disease (PD) is a degenerative disorder characterized by the progressive degeneration of dopamine-containing cells in substantia nigra, and it is the second most common neurodegenerative disorder worldwide. It can be difficult to differentiate between idiopathic PD and Atypical Parkinsonian syndromes (APS). In a high percentage of APS patients, the right diagnosis is not established even during late stages of the disease. Currently there is no specific test to verify PD, especially in the early stages of the disease.

    The aim was to verify if 123I-FP-CIT, DaTSCAN ® can differentiate early stages of Parkinson's disease as well as patients with Atypical Parkinsonian syndromes from manifest Parkinson's disease.

    Materials and methods: 121 consecutive patients were investigated with 123I-FP-CIT SPECT, during a four year period. All patients were diagnosed according to the established consensus criteria for diagnosis of Parkinson's disease (PD), (n=53), Atypical Parkinsonian syndromes (APS) (n=18). Remaining patients were grouped early PD (before onset the of L-dopa medication), (n=20), and non-PD syndromes (n=30). SPECT images were analysed visually according to a predefined ranking scale of dopaminergic degeneration, distinguishing a posterior-anterior degeneration pattern (egg shape) to a more global and severe degeneration pattern (burst striatum). Striatum ratios were quantitatively analysed with the 3D software, EXINI.

    Results: In the group of APS patients the burst striatum pattern was most frequent and found in 61% (11/18 patients). In PD patients the egg shape pattern was dominating, especially in early PD where it was present in 95% (19/20 patients). The sensitivity of burst striatum degeneration pattern was 61% (95%-CI 36-83%), specificity 90% (95%-CI 81-96%). The sensitivity of egg shape pattern was 74% (95%-CI 62-84%), specificity 90% (95%-CI 47-90%). The uptake ratios were reduced in both PD and APS patients and closely related to the image pattern. The lowest putamen/caudate ratio was found in early PD.

    Conclusion: In this study we found that in more than half of the patients it was possible to differentiate between PD and APS by visual interpretation only. Similar results were obtained using semi-quantitative uptake ratios, but combining visual assessment with uptake ratios did not add to the discriminating power of DATSCAN ® SPECT in this material

    References: Kahraman D, Eggers C, Schicha H, Timmermann L, Schmidt M. Visual assessment of dopaminergic degeneration pattern in 123I-FP-CIT SPECT differentiates patients with atypical parkinsonian syndromes and idiopathic Parkinson's disease. J Neurol. 2012;259:251-60

  • 4.
    Engström, Elias
    et al.
    Linköping University, Faculty of Health Sciences. Linköping University, Department of Medicine and Health Sciences, Radiology . Linköping University, Center for Medical Image Science and Visualization, CMIV.
    Persson, Anders
    Linköping University, Faculty of Health Sciences. Linköping University, Department of Medicine and Health Sciences, Radiology . Östergötlands Läns Landsting, Centre for Medical Imaging, Department of Radiology UHL. Linköping University, Center for Medical Image Science and Visualization, CMIV.
    Berge, J
    Engvall, Jan
    Linköping University, Faculty of Health Sciences. Linköping University, Department of Medicine and Health Sciences, Clinical Physiology . Östergötlands Läns Landsting, Heart Centre, Department of Clinical Physiology. Linköping University, Center for Medical Image Science and Visualization, CMIV.
    Wigström, Lars
    Linköping University, Faculty of Health Sciences. Linköping University, Department of Medicine and Health Sciences, Clinical Physiology . Östergötlands Läns Landsting, Heart Centre, Department of Clinical Physiology.
    Zachrisson, Helene
    Linköping University, Faculty of Health Sciences. Linköping University, Department of Medicine and Health Sciences, Clinical Physiology . Östergötlands Läns Landsting, Heart Centre, Department of Clinical Physiology. Linköping University, Center for Medical Image Science and Visualization, CMIV.
    Dual-energy CT of ex-vivo tissue samples.2008In: Cardiovaskulära vårmötet,2008, 2008Conference paper (Refereed)
  • 5.
    Georgiopoulos, Charalampos
    et al.
    Linköping University, Department of Medical and Health Sciences, Division of Radiological Sciences. Linköping University, Faculty of Medicine and Health Sciences. Region Östergötland, Center for Diagnostics, Department of Radiology in Linköping.
    Davidsson, Anette
    Linköping University, Department of Medical and Health Sciences, Division of Cardiovascular Medicine. Linköping University, Faculty of Health Sciences. Östergötlands Läns Landsting, Heart and Medicine Center, Department of Clinical Physiology in Linköping.
    Engström, Maria
    Linköping University, Department of Medical and Health Sciences, Division of Radiological Sciences. Linköping University, Faculty of Health Sciences. Linköping University, Center for Medical Image Science and Visualization (CMIV).
    Larsson, Elna-Marie
    Uppsala University, Sweden.
    Zachrisson, Helene
    Linköping University, Department of Medical and Health Sciences, Division of Cardiovascular Medicine. Linköping University, Faculty of Health Sciences. Region Östergötland, Heart and Medicine Center, Department of Clinical Physiology in Linköping. Linköping University, Center for Medical Image Science and Visualization (CMIV).
    Dizdar (Dizdar Segrell), Nil
    Linköping University, Department of Clinical and Experimental Medicine, Division of Neuro and Inflammation Science. Linköping University, Faculty of Medicine and Health Sciences. Region Östergötland, Local Health Care Services in Central Östergötland, Department of Neurology.
    The diagnostic value of dopamine transporter imaging and olfactory testing in patients with parkinsonian syndromes2015In: Journal of Neurology, ISSN 0340-5354, E-ISSN 1432-1459, Vol. 262, no 9, p. 2154-2163Article in journal (Refereed)
    Abstract [en]

    The aim of the study was to compare the efficacy of olfactory testing and presynaptic dopamine imaging in diagnosing Parkinsons disease (PD) and atypical parkinsonian syndromes (APS); to evaluate if the combination of these two diagnostic tools can improve their diagnostic value. A prospective investigation of 24 PD patients, 16 APS patients and 15 patients with non-parkinsonian syndromes was performed during an 18-month period. Single photon emission computed tomography with the presynaptic radioligand I-123-FP-CIT (DaTSCAN (R)) and olfactory testing with the Brief 12-item Smell Identification Test (B-SIT) were performed in all patients. DaTSCAN was analysed semi-quantitatively, by calculating two different striatal uptake ratios, and visually according to a predefined ranking scale. B-SIT score was significantly lower for PD patients, but not significantly different between APS and non-parkinsonism. The visual assessment of DaTSCAN had higher sensitivity, specificity and diagnostic accuracy compared to olfactory testing. Most PD patients (75 %) had visually predominant dopamine depletion in putamen, while most APS patients (56 %) had visually severe dopamine depletion both in putamen and in caudate nucleus. The combination of DaTSCAN and B-SIT led to a higher rate of correctly classified patients. Olfactory testing can distinguish PD from non-parkinsonism, but not PD from APS or APS from non-parkinsonism. DaTSCAN is more efficient than olfactory testing and can be valuable in differentiating PD from APS. However, combining olfactory testing and DaTSCAN imaging has a higher predictive value than these two methods separately.

  • 6.
    Georgiopoulos, Charalampos
    et al.
    Linköping University, Department of Medical and Health Sciences, Division of Radiological Sciences. Linköping University, Faculty of Medicine and Health Sciences. Region Östergötland, Center for Diagnostics, Department of Radiology in Linköping.
    Davidsson, Anette
    Linköping University, Department of Medical and Health Sciences, Clinical Physiology. Linköping University, Faculty of Health Sciences. Östergötlands Läns Landsting, Heart and Medicine Center, Department of Clinical Physiology in Linköping.
    Granerus, Göran
    Linköping University, Department of Medical and Health Sciences, Clinical Physiology. Linköping University, Faculty of Health Sciences. Östergötlands Läns Landsting, Heart and Medicine Center, Department of Clinical Physiology in Linköping.
    Dizdar (Dizdar Segrell), Nil
    Östergötlands Läns Landsting, Center for Diagnostics, Department of Clinical Chemistry.
    Zachrisson, Helene
    Linköping University, Department of Medical and Health Sciences, Clinical Physiology. Linköping University, Faculty of Health Sciences. Östergötlands Läns Landsting, Heart and Medicine Center, Department of Clinical Physiology in Linköping.
    DaTSCAN SPECT EVALUATION OF PATIENTS WITH MOVEMENT DISORDERS2011In: EUROPEAN JOURNAL OF NEUROLOGY, Wiley-Blackwell, 2011, Vol. 18 (Suppl. 2), no SI, p. 567-567, article id P2617Conference paper (Other academic)
    Abstract [en]

    Introduction: Molecular imaging with DaTSCAN SPECTis widely used as a diagnostic tool in patients with movementdisorders in the form of Parkinson's Disease (PD),Parkinson-plus syndromes and Tremor. In the present studythe potency of DATScan SPECT to detect degeneration inthe basal ganglia in early stages of PD, before the onset ofmedication, is evaluated. In addition the efficacy ofDaTSCAN for differential diagnosis between patients withidiopathic PD and patients with Parkinson-plus syndromesis examined.

    Methodology: Participants: 21 patients with PD in earlystages, before the onset of medication, 20 patients withidiopathic PD and 6 patients with Parkinson-plussyndromes. 15 participants with normal results ofDaTSCAN SPECT and a clinical diagnosis different fromPD or Parkinson-plus were used as control.

    DaTSCAN SPECT: In the present study the quantificationof Striatum Occipital/Occipital and the Xeleris workstation(GE) were used.

    Results: The quantification for patients with idiopathic PD(1.185±0.05687) was significantly lower (p<0.0001) fromthe control (2.369±0.1258) and significantly lower (p<0.05)from that of patients in early stages of PD, before the onsetof medication (1.359±0.05324). There was no significantdifference between the idiopathic PD and Parkinson-plussyndromes (1.103±0.2442).

    Conclusion: DaTSCAN SPECT can detect efficiently earlydegeneration in the basal ganglia before the onset ofmedication is needed. Its efficacy for the differentialdiagnosis between idiopathic PD and Parkinson-plussyndromes is questioned. The combination of imaging andclinical examination is mandatory for a certain diagnosis.

  • 7.
    Georgiopoulos, Charalampos
    et al.
    Linköping University, Department of Medical and Health Sciences, Division of Radiological Sciences. Linköping University, Faculty of Medicine and Health Sciences. Region Östergötland, Center for Diagnostics, Department of Radiology in Linköping.
    Warntjes, Marcel Jan Bertus
    Linköping University, Department of Medical and Health Sciences, Division of Cardiovascular Medicine. Linköping University, Faculty of Medicine and Health Sciences. Region Östergötland, Heart and Medicine Center, Department of Clinical Physiology in Linköping. Linköping University, Center for Medical Image Science and Visualization (CMIV). SyntheticMR AB, Linkoping, Sweden.
    Dizdar Segrell, Nil
    Linköping University, Department of Clinical and Experimental Medicine, Division of Neuro and Inflammation Science. Linköping University, Faculty of Medicine and Health Sciences. Region Östergötland, Local Health Care Services in Central Östergötland, Department of Neurology.
    Zachrisson, Helene
    Linköping University, Department of Medical and Health Sciences, Division of Cardiovascular Medicine. Linköping University, Faculty of Medicine and Health Sciences. Region Östergötland, Heart and Medicine Center, Department of Clinical Physiology in Linköping. Linköping University, Center for Medical Image Science and Visualization (CMIV).
    Engström, Maria
    Linköping University, Department of Medical and Health Sciences, Division of Radiological Sciences. Linköping University, Faculty of Medicine and Health Sciences. Linköping University, Center for Medical Image Science and Visualization (CMIV).
    Haller, Sven
    Affidea CDRC Centre Diagnost Radiol Carouge SA, Switzerland; Uppsala University, Sweden.
    Larsson, Elna-Marie
    Uppsala University, Sweden.
    Olfactory Impairment in Parkinsons Disease Studied with Diffusion Tensor and Magnetization Transfer Imaging2017In: Journal of Parkinson's Disease, ISSN 1877-7171, E-ISSN 1877-718X, Vol. 7, no 2, p. 301-311Article in journal (Refereed)
    Abstract [en]

    Background: Olfactory impairment is an early manifestation of Parkinsons disease (PD). Diffusion Tensor Imaging (DTI) and Magnetization Transfer (MT) are two imaging techniques that allow noninvasive detection of microstructural changes in the cerebral white matter. Objective: To assess white matter alterations associated with olfactory impairment in PD, using a binary imaging approach with DTI and MT. Methods: 22 PD patients and 13 healthy controls were examined with DTI, MT and an odor discrimination test. DTI data were first analyzed with tract-based spatial statistics (TBSS) in order to detect differences in fractional anisotropy, mean, radial and axial diffusivity between PD patients and controls. Voxelwise randomized permutation was employed for the MT analysis, after spatial and intensity normalization. Additionally, ROI analysis was performed on both the DTI and MT data, focused on the white matter adjacent to olfactory brain regions. Results: Whole brain voxelwise analysis revealed decreased axial diffusivity in the left uncinate fasciculus and the white matter adjacent to the left olfactory sulcus of PD patients. ROI analysis demonstrated decreased axial diffusivity in the right orbitofrontal cortex, as well as decreased mean diffusivity and axial diffusivity in the white matter of the left entorhinal cortex of PD patients. There were no significant differences regarding fractional anisotropy, radial diffusivity or MT between patients and controls. Conclusions: ROI analysis of DTI could detect microstructural changes in the white matter adjacent to olfactory areas in PD patients, whereas MT imaging could not.

  • 8.
    Georgiopoulos, Charalampos
    et al.
    Linköping University, Department of Medical and Health Sciences, Division of Radiological Sciences. Linköping University, Faculty of Medicine and Health Sciences. Region Östergötland, Center for Diagnostics, Department of Radiology in Linköping. Linköping University, Center for Medical Image Science and Visualization (CMIV).
    Witt, Suzanne
    Linköping University, Center for Medical Image Science and Visualization (CMIV). Linköping University, Faculty of Medicine and Health Sciences.
    Haller, Sven
    Ctr Imagerie Rive Droite SA, Switzerland; Uppsala Univ, Sweden.
    Dizdar Segrell, Nil
    Linköping University, Department of Clinical and Experimental Medicine, Division of Neuro and Inflammation Science. Linköping University, Faculty of Medicine and Health Sciences. Region Östergötland, Local Health Care Services in Central Östergötland, Department of Neurology in Linköping.
    Zachrisson, Helene
    Linköping University, Department of Medical and Health Sciences, Division of Cardiovascular Medicine. Linköping University, Faculty of Medicine and Health Sciences. Region Östergötland, Heart and Medicine Center, Department of Clinical Physiology in Linköping.
    Engström, Maria
    Linköping University, Department of Medical and Health Sciences, Division of Radiological Sciences. Linköping University, Faculty of Medicine and Health Sciences. Linköping University, Center for Medical Image Science and Visualization (CMIV).
    Larsson, Elna-Marie
    Uppsala Univ, Sweden.
    A study of neural activity and functional connectivity within the olfactory brain network in Parkinsons disease2019In: NeuroImage: Clinical, ISSN 0353-8842, E-ISSN 2213-1582, Vol. 23, article id UNSP 101946Article in journal (Refereed)
    Abstract [en]

    Olfactory dysfunction is an early manifestation of Parkinsons disease (PD). The present study aimed to illustrate potential differences between PD patients and healthy controls in terms of neural activity and functional connectivity within the olfactory brain network. Twenty PD patients and twenty healthy controls were examined with olfactory fMRI and resting-state fMRI. Data analysis of olfactory fMRI included data-driven tensorial independent component (ICA) and task-driven general linear model (GLM) analyses. Data analysis of resting-state fMRI included probabilistic ICA based on temporal concatenation and functional connectivity analysis within the olfactory network. ICA of olfactory fMRI identified an olfactory network consisting of the posterior piriform cortex, insula, right orbitofrontal cortex and thalamus. Recruitment of this network was less significant for PD patients. GLM analysis revealed significantly lower activity in the insula bilaterally and the right orbitofrontal cortex in PD compared to healthy controls but no significant differences in the olfactory cortex itself. Analysis of resting-state fMRI did not reveal any differences in the functional connectivity within the olfactory, default mode, salience or central executive networks between the two groups. In conclusion, olfactory dysfunction in PD is associated with less significant recruitment of the olfactory brain network. ICA could demonstrate differences in both the olfactory cortex and its main projections, compared to GLM that revealed differences only on the latter. Resting-state fMRI did not reveal any significant differences in functional connectivity within the olfactory, default mode, salience and central executive networks in this cohort.

  • 9.
    Georgiopoulos, Charalampos
    et al.
    Linköping University, Department of Medical and Health Sciences, Division of Radiological Sciences. Linköping University, Faculty of Medicine and Health Sciences. Region Östergötland, Center for Diagnostics, Department of Radiology in Linköping. Linköping University, Center for Medical Image Science and Visualization (CMIV).
    Witt, Suzanne Tyson
    Linköping University, Center for Medical Image Science and Visualization (CMIV).
    Haller, Sven
    Affidea CDRC Ctr Diagnost Radiol Carouge SA, Switzerland; Uppsala Univ, Sweden.
    Dizdar Segrell, Nil
    Linköping University, Department of Clinical and Experimental Medicine, Division of Neuro and Inflammation Science. Linköping University, Faculty of Medicine and Health Sciences. Region Östergötland, Local Health Care Services in Central Östergötland, Department of Neurology.
    Zachrisson, Helene
    Linköping University, Department of Medical and Health Sciences, Division of Cardiovascular Medicine. Linköping University, Faculty of Medicine and Health Sciences. Region Östergötland, Heart and Medicine Center, Department of Clinical Physiology in Linköping.
    Engström, Maria
    Linköping University, Department of Medical and Health Sciences, Division of Radiological Sciences. Linköping University, Faculty of Medicine and Health Sciences. Linköping University, Center for Medical Image Science and Visualization (CMIV).
    Larsson, Elna-Marie
    Uppsala Univ, Sweden.
    Olfactory fMRI: Implications of Stimulation Length and Repetition Time2018In: Chemical Senses, ISSN 0379-864X, E-ISSN 1464-3553, Vol. 43, no 6, p. 389-398Article in journal (Refereed)
    Abstract [en]

    Studying olfaction with functional magnetic resonance imaging (fMRI) poses various methodological challenges. This study aimed to investigate the effects of stimulation length and repetition time (TR) on the activation pattern of 4 olfactory brain regions: the anterior and the posterior piriform cortex, the orbitofrontal cortex, and the insula. Twenty-two healthy participants with normal olfaction were examined with fMRI, with 2 stimulation lengths (6 s and 15 s) and 2 TRs (0.901 s and 1.34 s). Data were analyzed using General Linear Model (GLM), Tensorial Independent Component Analysis (TICA), and by plotting the event-related time course of brain activation in the 4 olfactory regions of interest. The statistical analysis of the time courses revealed that short TR was associated with more pronounced signal increase and short stimulation was associated with shorter time to peak signal. Additionally, both long stimulation and short TR were associated with oscillatory time courses, whereas both short stimulation and short TR resulted in more typical time courses. GLM analysis showed that the combination of short stimulation and short TR could result in visually larger activation within these olfactory areas. TICA validated that the tested paradigm was spatially and temporally associated with a functionally connected network that included all 4 olfactory regions. In conclusion, the combination of short stimulation and short TR is associated with higher signal increase and shorter time to peak, making it more amenable to standard GLM-type analyses than long stimulation and long TR, and it should, thus, be preferable for olfactory fMRI.

  • 10.
    Gustafsson, Agneta
    et al.
    Linköping University, Faculty of Health Sciences. Linköping University, Department of Medicine and Health Sciences. Östergötlands Läns Landsting, Centre of Surgery and Oncology, Department of Radiation Physics.
    Granerus, Göran
    Linköping University, Faculty of Health Sciences. Linköping University, Department of Medicine and Health Sciences, Clinical Physiology . Östergötlands Läns Landsting, Heart Centre, Department of Clinical Physiology.
    Zachrisson, Helene
    Linköping University, Faculty of Health Sciences. Linköping University, Department of Medicine and Health Sciences, Clinical Physiology . Östergötlands Läns Landsting, Heart Centre, Department of Clinical Physiology.
    Evaluation of the OSEM reconstruction techniques used in DATscan.2008In: Nuklearmedicinska vårmötet,2008, 2008Conference paper (Refereed)
  • 11.
    Gustafsson, Håkan
    et al.
    Linköping University, Department of Medical and Health Sciences, Radiology. Linköping University, Faculty of Health Sciences. Linköping University, Center for Medical Image Science and Visualization (CMIV).
    Berg, Kirsti
    Norwegian University of Science and Technology.
    Lindgren, Mikael
    Norwegian University of Science and Technology.
    Engström, Maria
    Linköping University, Department of Medical and Health Sciences, Radiology. Linköping University, Faculty of Health Sciences. Linköping University, Center for Medical Image Science and Visualization (CMIV).
    De Muinck, Ebo
    Linköping University, Department of Medical and Health Sciences. Linköping University, Faculty of Health Sciences. Linköping University, Center for Medical Image Science and Visualization (CMIV).
    Zachrisson, Helene
    Linköping University, Department of Medical and Health Sciences, Clinical Physiology. Linköping University, Faculty of Health Sciences. Östergötlands Läns Landsting, Heart and Medicine Center, Department of Clinical Physiology in Linköping. Linköping University, Center for Medical Image Science and Visualization (CMIV).
    Fe(3+) Heterogeneity in Ex Vivo Carotid Atherosclerotic Plaques2011In: Free Radical Biology & Medicine, ISSN 0891-5849, E-ISSN 1873-4596, Vol. 51, no Suppl. 1, p. S40-S40Article in journal (Other academic)
    Abstract [en]

    n/a

  • 12.
    Gustafsson, Håkan
    et al.
    Linköping University, Department of Medical and Health Sciences, Division of Radiological Sciences. Linköping University, Faculty of Health Sciences. Östergötlands Läns Landsting, Center for Diagnostics, Department of Biomedical Engineering. Linköping University, Center for Medical Image Science and Visualization (CMIV).
    Hallbeck, Martin
    Linköping University, Department of Clinical and Experimental Medicine, Division of Neuro and Inflammation Science. Linköping University, Faculty of Medicine and Health Sciences. Region Östergötland, Center for Diagnostics, Department of Clinical Pathology and Clinical Genetics.
    Lindgren, Mikael
    Linköping University, Department of Physics, Chemistry and Biology, Chemistry. Linköping University, The Institute of Technology. Norwegian University of Science and Technology, Norway.
    Kolbun, Natallia
    Linköping University, Department of Medical and Health Sciences, Division of Radiological Sciences. Linköping University, Faculty of Health Sciences. Linköping University, Center for Medical Image Science and Visualization (CMIV).
    Jonson, Maria
    Linköping University, Department of Physics, Chemistry and Biology, Chemistry. Linköping University, The Institute of Technology.
    Engström, Maria
    Linköping University, Department of Medical and Health Sciences, Division of Radiological Sciences. Linköping University, Faculty of Health Sciences. Linköping University, Center for Medical Image Science and Visualization (CMIV).
    de Muinck, Ebo
    Linköping University, Faculty of Health Sciences. Linköping University, Department of Medical and Health Sciences, Division of Cardiovascular Medicine. Region Östergötland, Heart and Medicine Center, Department of Cardiology in Linköping.
    Zachrisson, Helene
    Linköping University, Department of Medical and Health Sciences, Division of Cardiovascular Medicine. Linköping University, Faculty of Health Sciences. Region Östergötland, Heart and Medicine Center, Department of Clinical Physiology in Linköping.
    Visualization of oxidative stress in ex vivo biopsies using electron paramagnetic resonance imaging2015In: Magnetic Resonance in Medicine, ISSN 0740-3194, E-ISSN 1522-2594, Vol. 73, no 4, p. 1682-1691Article in journal (Refereed)
    Abstract [en]

    PURPOSE: The purpose of this study was to develop an X-Band electron paramagnetic resonance imaging protocol for visualization of oxidative stress in biopsies.

    METHODS: The developed electron paramagnetic resonance imaging protocol was based on spin trapping with the cyclic hydroxylamine spin probe 1-hydroxy-3-methoxycarbonyl-2,2,5,5-tetramethylpyrrolidine and X-Band EPR imaging. Computer software was developed for deconvolution and back-projection of the EPR image. A phantom containing radicals of known spatial characteristic was used for evaluation of the developed protocol. As a demonstration of the technique electron paramagnetic resonance imaging of oxidative stress was performed in six sections of atherosclerotic plaques. Histopathological analyses were performed on adjoining sections.

    RESULTS: The developed computer software for deconvolution and back-projection of the EPR images could accurately reproduce the shape of a phantom of known spatial distribution of radicals. The developed protocol could successfully be used to image oxidative stress in six sections of the three ex vivo atherosclerotic plaques.

    CONCLUSIONS: We have shown that oxidative stress can be imaged using a combination of spin trapping with the cyclic hydroxylamine spin probe cyclic hydroxylamine spin probe 1-hydroxy-3-methoxycarbonyl-2,2,5,5-tetramethylpyrrolidine and X-Band EPR imaging. A thorough and systematic evaluation on different types of biopsies must be performed in the future to validate the proposed technique. Magn Reson Med, 2014.

  • 13.
    Gustafsson, Håkan
    et al.
    Linköping University, Center for Medical Image Science and Visualization (CMIV). Linköping University, Department of Medical and Health Sciences, Division of Radiological Sciences. Linköping University, Faculty of Health Sciences.
    Hallbeck, Martin
    Linköping University, Department of Clinical and Experimental Medicine, Division of Inflammation Medicine. Linköping University, Faculty of Health Sciences. Östergötlands Läns Landsting, Center for Diagnostics, Department of Clinical Pathology and Clinical Genetics.
    Norell, M.
    Linköping University, Department of Medical and Health Sciences, Division of Cardiovascular Medicine. Linköping University, Faculty of Health Sciences.
    Lindgren, Mikael
    Norwegian University of Science and Technology, Trondheim, Norway.
    Engström, Maria
    Linköping University, Center for Medical Image Science and Visualization (CMIV). Linköping University, Department of Medical and Health Sciences, Division of Radiological Sciences. Linköping University, Faculty of Health Sciences.
    Rosén, Anders
    Linköping University, Department of Clinical and Experimental Medicine, Division of Cell Biology. Linköping University, Faculty of Health Sciences.
    Zachrisson, Helene
    Linköping University, Center for Medical Image Science and Visualization (CMIV). Linköping University, Department of Medical and Health Sciences, Division of Cardiovascular Medicine. Linköping University, Faculty of Health Sciences. Östergötlands Läns Landsting, Heart and Medicine Center, Department of Clinical Physiology in Linköping.
    Fe(III) distribution varies substantially within and between atherosclerotic plaques2014In: Magnetic Resonance in Medicine, ISSN 0740-3194, E-ISSN 1522-2594, Vol. 2, no 71, p. 885-892Article in journal (Refereed)
    Abstract [en]

    PURPOSE:

    Vulnerable atherosclerotic plaques are structurally weak and prone to rupture, presumably due to local oxidative stress. Redox active iron is linked to oxidative stress and the aim of this study was to investigate the distribution of Fe(III) in carotid plaques and its relation to vulnerability for rupture.

    METHODS:

    Atherosclerotic plaques from 10 patients (three asymptomatic and seven symptomatic) were investigated. Plaque vulnerability was classified using ultrasound and immunohistochemistry and correlated to Fe(III) measured by electron paramagnetic resonance spectroscopy.

    RESULTS:

    Large intra-plaque Fe(III) variations were found. Plaques from symptomatic patients had a higher Fe(III) concentration as compared with asymptomatic plaques (0.36 ± 0.21 vs. 0.06 ± 0.04 nmol Fe(III)/mg tissue, P < 0.05, in sections adjoining narrowest part of the plaques). All but one plaque from symptomatic patients showed signs of cap rupture. No plaque from asymptomatic patients showed signs of cap rupture. There was a significant increase in cap macrophages in plaques from symptomatic patients compared with asymptomatic patients (31 ± 11% vs. 2.3 ± 2.3%, P < 0.01).

    CONCLUSION:

    Fe(III) distribution varies substantially within atherosclerotic plaques. Plaques from symptomatic patients had significantly higher concentrations of Fe(III), signs of cap rupture and increased cap macrophage activity.

  • 14.
    Gustafsson, Håkan
    et al.
    Linköping University, Center for Medical Image Science and Visualization, CMIV. Linköping University, Department of Medical and Health Sciences, Radiology. Linköping University, Faculty of Health Sciences.
    Norell, M.
    Linköping University, Department of Medical and Health Sciences, Clinical Physiology. Linköping University, Faculty of Health Sciences.
    Lindgren, M.
    Linköping University, Department of Physics, Chemistry and Biology. Linköping University, The Institute of Technology.
    Engström, Maria
    Linköping University, Center for Medical Image Science and Visualization, CMIV. Linköping University, Department of Medical and Health Sciences, Radiology. Linköping University, Faculty of Health Sciences.
    Rosén, A.
    Linköping University, Department of Clinical and Experimental Medicine. Linköping University, Faculty of Health Sciences.
    Zachrisson, Helene
    Linköping University, Department of Medical and Health Sciences, Clinical Physiology. Linköping University, Faculty of Health Sciences. Östergötlands Läns Landsting, Heart and Medicine Centre, Department of Clinical Physiology UHL.
    Is vulnerability for carotid plaque rupture related to intrinsic Fe (III) distribution2012Conference paper (Other academic)
    Abstract [en]

    Atherosclerotic plaques vulnerable for rupture are characterised by e.g., a large lipid pole, a high concentration of inflammatory cells and a thin fibrous cap. Recent research has showed that vulnerable plaques are structurally weaker and therefore more likely to rupture in response to physical forces; possible due to high local concentrations of macrophages and reactive oxygen species (ROS).  It is well known that redox active iron catalyses production of ROS and that the presence of Fe(III) is linked to ROS production. The aim of this study was to investigate the distribution of Fe(III) in carotid plaques.

  • 15.
    Hallman, Daniel
    et al.
    Linköping University, Faculty of Health Sciences. Linköping University, Department of Medicine and Care, Physiology.
    Neider, Daniel
    Linköping University, Faculty of Health Sciences. Linköping University, Department of Medicine and Care, Physiology.
    Zachrisson, Helene
    Linköping University, Faculty of Health Sciences. Linköping University, Department of Medicine and Care, Clinical Physiology. Östergötlands Läns Landsting, Heart Centre, Department of Clinical Physiology.
    Lindenberger, Marcus
    Linköping University, Faculty of Health Sciences. Linköping University, Department of Medicine and Care, Physiology.
    Länne, Toste
    Linköping University, Faculty of Health Sciences. Linköping University, Department of Medicine and Care, Physiology. Östergötlands Läns Landsting, Heart Centre, Department of Thoracic and Vascular Surgery.
    Diameter and compliance of the greater saphenous vein - Effect of age and Glyceryl trinitrates.2007In: Kardiovaskulära vårmötet,2007, 2007Conference paper (Other academic)
  • 16.
    Hasib, Lekbira
    et al.
    Linköping University, Faculty of Medicine and Health Sciences. Linköping University, Department of Medical and Health Sciences, Division of Cardiovascular Medicine.
    Lundberg, Anna
    Linköping University, Department of Medical and Health Sciences, Division of Cardiovascular Medicine. Linköping University, Faculty of Medicine and Health Sciences.
    Zachrisson, Helene
    Linköping University, Department of Medical and Health Sciences, Division of Cardiovascular Medicine. Linköping University, Faculty of Medicine and Health Sciences. Region Östergötland, Heart and Medicine Center, Department of Clinical Physiology in Linköping. Linköping University, Center for Medical Image Science and Visualization (CMIV).
    Ernerudh, Jan
    Linköping University, Department of Clinical and Experimental Medicine, Division of Neuro and Inflammation Science. Linköping University, Faculty of Medicine and Health Sciences. Region Östergötland, Center for Diagnostics, Department of Clinical Immunology and Transfusion Medicine.
    Jonasson, Lena
    Linköping University, Department of Medical and Health Sciences, Division of Cardiovascular Medicine. Linköping University, Faculty of Medicine and Health Sciences. Region Östergötland, Heart and Medicine Center, Department of Cardiology in Linköping.
    Functional and homeostatic defects of regulatory T cells in patients with coronary artery disease2016In: Journal of Internal Medicine, ISSN 0954-6820, E-ISSN 1365-2796, Vol. 279, no 1, p. 63-77Article in journal (Refereed)
    Abstract [en]

    ObjectiveRegulatory T cells (Tregs) are considered atheroprotective, and low levels have been associated with the acute coronary syndrome (ACS), particularly non-ST elevation (NSTE)-ACS. However, the functional properties as well as homeostasis of Tregs are mainly unknown in coronary artery disease (CAD). Here, we investigated the composition and functional properties of naive (n) and memory (m)Tregs in patients with NSTE-ACS and in patients 6-12months post-ACS. MethodsBased on the expression of CD25, FOXP3, CD127, CD45RA, CD39 and CTLA-4, Tregsubsets were defined by flow cytometry in whole blood or isolated CD4(+) T cells. The functional properties of nTregs and mTregs were examined in terms of proliferative capacity and modulation of cytokine secretion. To understand the potential consequences of Treg defects, we also investigated correlations with lipopolysaccharide (LPS)-induced cytokine secretion and ultrasound-defined carotid atherosclerosis. ResultsBoth NSTE-ACS and post-ACS patients exhibited reduced levels of nTregs (P&lt;0.001) compared with healthy control subjects, but without compensatory increases in mTregs. Both nTregs and mTregs from patients showed significantly lower replicative rates and impaired capacity to modulate T-cell proliferation and secretion of interferon-gamma and IL-10. The Treg defect was also associated with LPS-induced cytokine secretion and increased burden of carotid atherosclerosis. ConclusionOur results demonstrate a functional and homeostatic Treg defect in patients with NSTE-ACS and also in stabilized patients 6-12months after ACS. Moreover, this defect was associated with a subclinical proinflammatory and atherogenic state. We believe that the failure to preserve Treg function and homeostasis reflects a need for immune-restoring strategies in CAD.

  • 17. Jatuzis, D
    et al.
    Zachrisson, Helene
    Linköping University, Department of Medical and Health Sciences, Clinical Physiology. Linköping University, Faculty of Health Sciences. Linköping University, Center for Medical Image Science and Visualization (CMIV). Östergötlands Läns Landsting, Heart and Medicine Center, Department of Clinical Physiology in Linköping.
    Blomstrand, C
    Ekholm, S
    Holm, J
    Volkmann, R
    Evaluation of posterior cerebral artery blood flow with transcranial Doppler sonography: value and risk of common carotid artery compression.2000In: Journal of Clinical Ultrasound, ISSN 0091-2751, E-ISSN 1097-0096, Vol. 28, no 9, p. 452-460Article in journal (Refereed)
    Abstract [en]

    PURPOSE: Investigations of the posterior cerebral arteries (PCA) by transcranial Doppler sonography (TCD) may be less reliable than investigations of the anterior part of the circle of Willis. Nevertheless, a true PCA may be identified by manual compression of the proximal common carotid artery (CCA) during TCD. Therefore, we used CCA compression in clinically indicated TCD studies and assessed retrospectively its risks and prospectively its benefits for PCA evaluations.

    METHODS: Using the transtemporal approach, we prospectively assessed flow velocities in posteriorly located blood vessels in 180 consecutive patients before and during CCA compression. The complications of CCA compression were retrospectively reviewed in all 3,383 clinical TCD investigations performed over an 8-year period.

    RESULTS: Decreased flow velocities during ipsilateral CCA compression occurred in 17% of patients. A PCA-like vessel with perfusion from the carotid artery or PCA supply from the carotid circulation was unmasked. Mixed distal PCA support by the posterior communicating artery and proximal PCA could not be shown by TCD. Transient cerebral symptoms occurred in less than 0.4% of the 3,383 retrospectively reviewed TCD investigations; no other adverse effects were seen.

    CONCLUSIONS: TCD without CCA compression may lead to false identification of the PCA. Since transient cerebral symptoms during CCA compression are rare, CCA compression can be used when a clinical TCD investigation of intracranial collateral blood flow compensation is indicated or when the identification of a cerebral artery is uncertain.

  • 18.
    Jogestrand, T.
    et al.
    Karolinska universitetssjuk­huset, Huddinge, Stockholm.
    Freden-Lindkvist, J.
    Sahlgrenska universitetssjukhuset, Göteborg.
    Lindqvist, M.
    ­Karolinska universitetssjukhuset, Solna, Stockholm.
    Lundgren, S.
    ­Blekingesjukhuset, Karlskrona.
    Sundby, A.
    ­Norrlands ­universitetssjukhus, Umeå.
    Tillman, Ann-Sofie
    Östergötlands Läns Landsting, Heart and Medicine Centre, Department of Cardiology VHN.
    Zachrisson, Helene
    Linköping University, Center for Medical Image Science and Visualization, CMIV. Linköping University, Department of Medical and Health Sciences, Clinical Physiology. Linköping University, Faculty of Health Sciences. Östergötlands Läns Landsting, Heart and Medicine Centre, Department of Clinical Physiology UHL.
    Equalis kriterier för karotisdiagnostik – under kontinuerlig uppgradering2012In: Läkartidningen, ISSN 0023-7205, E-ISSN 1652-7518, Vol. 109, no 13, p. 702-703Article in journal (Refereed)
    Abstract [sv]

    Ultraljudsundersökning av karotisartärerna med så­­ ­kallad duplexteknik har använts i Sverige sedan början av 1980-talet. Equalis expertgrupp för ­fysiologisk kärldia­gnostik har nyligen presen­terat sina rekommendationer för karotisdiagnostik med ultra­ljudsteknik.

  • 19.
    Jogestrand, Tomas
    et al.
    Karolinska Institute, Sweden; Karolinska University Hospital, Sweden.
    Freden-Lindqvist, Johan
    Sahlgrens University Hospital, Sweden.
    Lindqvist, Madeleine
    Karolinska University Hospital, Sweden.
    Lundgren, Susanne
    Blekingesjukhuset, Sweden.
    Tillman, Ann-Sofie
    Region Östergötland, Center for Diagnostics, Department of Clinical Physiology in Norrköping.
    Zachrisson, Helene
    Linköping University, Department of Medical and Health Sciences, Division of Cardiovascular Medicine. Linköping University, Faculty of Health Sciences. Region Östergötland, Heart and Medicine Center, Department of Clinical Physiology in Linköping. Linköping University, Center for Medical Image Science and Visualization (CMIV).
    Discrepancies in recommended criteria for grading of carotid stenosis with ultrasound2016In: Clinical Physiology and Functional Imaging, ISSN 1475-0961, E-ISSN 1475-097X, Vol. 36, no 4, p. 326-329Article in journal (Refereed)
    Abstract [en]

    The accuracy of duplex ultrasound for grading of internal carotid artery stenosis has been widely tested and shown to be high. However, different methods for measurement of the degree of carotid stenosis with the golden standard conventional angiography have been used in the different studies. This, together with other factors, has led to some confusion regarding the relation between the ultrasonographically measured flow velocity and the angiographically measured degree of stenosis. The ultrasound criteria that are used in Sweden (and in Germany) differ in an important way from the criteria recommended in North America and the United Kingdom for the same degree of angiographic stenoses. Possible reasons for the discrepancies are discussed in this article. The authors recommend absolute agreement locally whether ECST or NASCET criteria shall be used in the communication between radiologists, clinical physiologists, vascular surgeons, neurologists and other physicians involved in patient management decisions. Angle-dependent ultrasound criteria should be used and flow velocity measurements with ultrasound should be combined with assessment of plaque burden on 2D picture.

  • 20.
    Koppal, Sandeep
    et al.
    Linköping University, Center for Medical Image Science and Visualization (CMIV). Linköping University, Department of Medical and Health Sciences, Division of Cardiovascular Medicine. Linköping University, Faculty of Medicine and Health Sciences.
    Warntjes, Marcel
    Linköping University, Center for Medical Image Science and Visualization (CMIV). Linköping University, Department of Medical and Health Sciences, Division of Cardiovascular Medicine. Linköping University, Faculty of Medicine and Health Sciences. Region Östergötland, Heart and Medicine Center, Department of Clinical Physiology in Linköping. SyntheticMR AB, Linköping, Sweden.
    Swann, Jeremy
    School of Computing, University of Leeds, Leeds, United Kingdom.
    Dyverfeldt, Petter
    Linköping University, Center for Medical Image Science and Visualization (CMIV). Linköping University, Department of Medical and Health Sciences, Division of Cardiovascular Medicine. Linköping University, Faculty of Medicine and Health Sciences. Region Östergötland, Heart and Medicine Center, Department of Clinical Physiology in Linköping.
    Kihlberg, Johan
    Linköping University, Center for Medical Image Science and Visualization (CMIV). Region Östergötland, Center for Diagnostics, Department of Radiology in Linköping. Linköping University, Department of Medical and Health Sciences, Division of Radiological Sciences. Linköping University, Faculty of Medicine and Health Sciences.
    Moreno, Rodrigo
    Linköping University, Center for Medical Image Science and Visualization (CMIV). KTH, Royal Institute of Technology, Stockholm, Sweden.
    Magee, Derek
    School of Computing, University of Leeds, Leeds, United Kingdom.
    Roberts, Nicholas
    Division of Brain Sciences, Department of Medicine, Institute of Neurology, Imperial College, London, United Kingdom.
    Zachrisson, Helene
    Linköping University, Center for Medical Image Science and Visualization (CMIV). Linköping University, Department of Medical and Health Sciences, Division of Cardiovascular Medicine. Linköping University, Faculty of Medicine and Health Sciences. Region Östergötland, Heart and Medicine Center, Department of Clinical Physiology in Linköping.
    Forssell, Claes
    Region Östergötland, Heart and Medicine Center, Department of Thoracic and Vascular Surgery.
    Länne, Toste
    Linköping University, Center for Medical Image Science and Visualization (CMIV). Linköping University, Department of Medical and Health Sciences, Division of Cardiovascular Medicine. Linköping University, Faculty of Medicine and Health Sciences. Region Östergötland, Heart and Medicine Center, Department of Thoracic and Vascular Surgery.
    Treanor, Darren
    Linköping University, Department of Clinical and Experimental Medicine, Division of Neuro and Inflammation Science. Linköping University, Faculty of Medicine and Health Sciences. Department of Pathology and Tumour Biology, Leeds Institute of Molecular Medicine, University of Leeds, Leeds, United Kingdom.
    de Muinck, Ebo
    Linköping University, Center for Medical Image Science and Visualization (CMIV). Linköping University, Department of Medical and Health Sciences, Division of Cardiovascular Medicine. Linköping University, Faculty of Medicine and Health Sciences. Region Östergötland, Heart and Medicine Center, Department of Cardiology in Linköping.
    Quantitative Fat and R2* Mapping In Vivo to Measure Lipid-Rich Necrotic Core and Intraplaque Hemorrhage in Carotid Atherosclerosis2017In: Magnetic Resonance in Medicine, ISSN 0740-3194, E-ISSN 1522-2594, Vol. 78, no 1, p. 285-296Article in journal (Refereed)
    Abstract [en]

    Purpose: The aim of this work was to quantify the extent of lipid-rich necrotic core (LRNC) and intraplaque hemorrhage (IPH) in atherosclerotic plaques.

    Methods: Patients scheduled for carotid endarterectomy underwent four-point Dixon and T1-weighted magnetic resonance imaging (MRI) at 3 Tesla. Fat and R2* maps were generated from the Dixon sequence at the acquired spatial resolution of 0.60 × 0.60 × 0.70 mm voxel size. MRI and three-dimensional (3D) histology volumes of plaques were registered. The registration matrix was applied to segmentations denoting LRNC and IPH in 3D histology to split plaque volumes in regions with and without LRNC and IPH.

    Results: Five patients were included. Regarding volumes of LRNC identified by 3D histology, the average fat fraction by MRI was significantly higher inside LRNC than outside: 12.64 ± 0.2737% versus 9.294 ± 0.1762% (mean ± standard error of the mean [SEM]; P < 0.001). The same was true for IPH identified by 3D histology, R2* inside versus outside IPH was: 71.81 ± 1.276 s−1 versus 56.94 ± 0.9095 s−1 (mean ± SEM; P < 0.001). There was a strong correlation between the cumulative fat and the volume of LRNC from 3D histology (R2 = 0.92) as well as between cumulative R2* and IPH (R2 = 0.94).

    Conclusion: Quantitative mapping of fat and R2* from Dixon MRI reliably quantifies the extent of LRNC and IPH.

  • 21.
    Lilledahl, Magnus B.
    et al.
    Norwegian University of Science and Technoogy, Norway.
    Gustafsson, Håkan
    Linköping University, Department of Medical and Health Sciences, Division of Radiological Sciences. Linköping University, Faculty of Health Sciences. Region Östergötland, Center for Diagnostics, Department of Biomedical Engineering.
    Gunnar Ellingsen, Pal
    Norwegian University of Science and Technoogy, Norway.
    Zachrisson, Helene
    Linköping University, Department of Medical and Health Sciences, Division of Cardiovascular Medicine. Linköping University, Faculty of Health Sciences. Region Östergötland, Heart and Medicine Center, Department of Clinical Physiology in Linköping.
    Hallbeck, Martin
    Linköping University, Department of Clinical and Experimental Medicine, Division of Neuro and Inflammation Science. Linköping University, Faculty of Medicine and Health Sciences. Region Östergötland, Center for Diagnostics, Department of Clinical Pathology and Clinical Genetics.
    Stenhjem Hagen, Vegard
    Norwegian University of Science and Technoogy, Norway.
    Kildemo, Morten
    Norwegian University of Science and Technoogy, Norway.
    Lindgren, Mikael
    Linköping University, Department of Physics, Chemistry and Biology, Chemistry. Linköping University, The Institute of Technology. Norwegian University of Science and Technoogy, Norway.
    Combined imaging of oxidative stress and microscopic structure reveals new features in human atherosclerotic plaques2015In: Journal of Biomedical Optics, ISSN 1083-3668, E-ISSN 1560-2281, Vol. 20, no 2, p. 020503-Article in journal (Refereed)
    Abstract [en]

    Human atherosclerotic samples collected by carotid endarterectomy were investigated using electronic paramagnetic resonance imaging (EPRI) for visualization of reactive oxygen species, and nonlinear optical microscopy (NLOM) to study structural features. Regions of strong EPRI signal, indicating a higher concentration of reactive oxygen species and increased inflammation, were found to colocalize with regions dense in cholesterol crystals as revealed by NLOM.

  • 22.
    Lindenberger, Marcus
    et al.
    Linköping University, Faculty of Health Sciences. Linköping University, Department of Medicine and Health Sciences, Physiology .
    Zachrisson, Helene
    Linköping University, Faculty of Health Sciences. Linköping University, Department of Medicine and Health Sciences, Clinical Physiology . Östergötlands Läns Landsting, Heart Centre, Department of Clinical Physiology.
    Neider, Daniel
    Linköping University, Faculty of Health Sciences. Linköping University, Department of Medicine and Health Sciences, Physiology .
    Länne, Toste
    Linköping University, Faculty of Health Sciences. Linköping University, Department of Medicine and Health Sciences, Physiology . Östergötlands Läns Landsting, Heart Centre, Department of Thoracic and Vascular Surgery.
    Venous compliance and wall distensibility in the venous compartments of the lower limb in man2008In: Experimental Biology,2008, 2008Conference paper (Refereed)
    Abstract [en]

      

  • 23.
    Lundberg, Anna K
    et al.
    Linköping University, Department of Medical and Health Sciences, Division of Cardiovascular Medicine. Linköping University, Faculty of Health Sciences.
    Jönsson, Simon
    Linköping University, Department of Medical and Health Sciences, Division of Cardiovascular Medicine. Linköping University, Faculty of Health Sciences.
    Zachrisson, Helene
    Östergötlands Läns Landsting, Heart and Medicine Center, Department of Clinical Physiology in Linköping.
    Kristenson, Margareta
    Linköping University, Department of Medical and Health Sciences, Division of Community Medicine. Linköping University, Faculty of Health Sciences.
    Jonasson, Lena
    Linköping University, Department of Medical and Health Sciences, Division of Cardiovascular Medicine. Linköping University, Faculty of Health Sciences. Östergötlands Läns Landsting, Heart and Medicine Center, Department of Cardiology in Linköping.
    Inflammatory response to acute mental stress is associated with altered cortisol reactivity and telomere shortening in patients with coronary artery diseaseManuscript (preprint) (Other academic)
    Abstract [en]

    Background: Psychological stress and inflammation are both important risk factors for coronary artery disease (CAD). Susceptibility to mental stress-induced inflammation has been little explored in patients with CAD. Here, we investigated whether stress-induced inflammatory response, more precisely neutrophil activation, was associated with cortisol reactivity, leukocyte telomere length (TL) and carotid atherosclerotic burden in CAD.

    Methods: Sixty-four patients with stable CAD underwent a laboratory stress test. Matrix metalloproteinase (MMP)-9, MMP-8, tissue inhibitors (TIMP)-1 and -2, myeloperoxidase (MPO) and salivary cortisol were measured before and 20 min after stress. Leukocyte TL was assessed as well as basal cortisol levels, background psychological factors and atherosclerosis in carotid arteries.

    Results: The variation in stress-induced release of neutrophil markers was substantial. Patients were therefore divided into lower and upper tertiles depending on changes in serum MMP-9, T1: -12 %, T3: +27 %, with corresponding changes in MMP-8 and MPO. Clinical or psychological characteristics did not differ between groups, neither did basal levels of neutrophil markers or cortisol. Cardiovascular reactivity during stress was similar in T1 and T3, while cortisol declined after stress only in T3 (-30 %). Leukocyte TL was shorter in T3 than in T1, 0.78 vs 0.88, p = 0.006. Moreover, presence of plaques in right carotid artery differed between T1 and T3, 66 % vs 100 %, p = 0.004.

    Conclusion: Stress-induced neutrophil activation in CAD patients was associated with altered cortisol reactivity, leukocyte telomere attrition and increased subclinical atherosclerosis. Data suggest that mental stress testing can identify high-risk patients in need of novel prevention and treatment strategies.

  • 24.
    Lundin, Evelyn S.
    et al.
    Linköping University, Department of Clinical and Experimental Medicine, Division of Clinical Sciences. Linköping University, Faculty of Health Sciences. Östergötlands Läns Landsting, Center of Paediatrics and Gynaecology and Obstetrics, Department of Gynaecology and Obstetrics in Linköping.
    Johansson, Torsten
    Linköping University, Department of Clinical and Experimental Medicine, Division of Inflammation Medicine. Linköping University, Faculty of Health Sciences. Östergötlands Läns Landsting, Center for Surgery, Orthopaedics and Cancer Treatment, Department of Orthopaedics in Linköping.
    Zachrisson, Helene
    Linköping University, Department of Medical and Health Sciences, Division of Cardiovascular Medicine. Linköping University, Faculty of Health Sciences. Östergötlands Läns Landsting, Heart and Medicine Center, Department of Clinical Physiology in Linköping.
    Leandersson, Ulf
    Kalmar County Hospital, Sweden .
    Backman, Fatma
    University Hospital, Sweden .
    Falknas, Laila
    Ryhov County Hospital, Sweden .
    Kjölhede, Preben
    Linköping University, Department of Clinical and Experimental Medicine, Division of Clinical Sciences. Linköping University, Faculty of Health Sciences. Östergötlands Läns Landsting, Center of Paediatrics and Gynaecology and Obstetrics, Department of Gynaecology and Obstetrics in Linköping.
    Single-dose tranexamic acid in advanced ovarian cancer surgery reduces blood loss and transfusions: double-blind placebo-controlled randomized multicenter study2014In: Acta Obstetricia et Gynecologica Scandinavica, ISSN 0001-6349, E-ISSN 1600-0412, Vol. 93, no 4, p. 335-344Article in journal (Refereed)
    Abstract [en]

    ObjectiveTo determine whether single-dose tranexamic acid given intravenously immediately before surgery for presumed advanced ovarian cancer reduces perioperative blood loss and blood transfusions. DesignA randomized double-blind, placebo-controlled multicenter study. SettingTwo university hospitals and two central hospitals in the southeast health region of Sweden. PopulationOne hundred women with presumed advanced ovarian cancer scheduled for radical debulking surgery between March 2008 and May 2012 who complied with inclusion/exclusion criteria were randomized; 50 were allocated to receive tranexamic acid and 50 to receive placebo. Analysis was performed according to intention-to-treat principles. MethodsThe volume of tranexamic acid (15mg/kg body weight, 100mg/mL tranexamic acid) or the same volume of placebo (0.9% NaCl) was added to a 100-mL saline solution plastic bag. The study medication was given immediately before the start of surgery. Data were analyzed by means of non-parametric statistics and multivariate models adjusted for confounding factors. Main outcome measuresBlood loss and red blood cell transfusions. ResultsThe total blood loss volume and transfusion rate were significantly lower in the tranexamic acid group compared with the placebo group. Median total blood loss was 520 and 730mL, respectively (p=0.03). Fifteen (30%) and 22 (44%), respectively received transfusions (odds ratio 0.44; upper 95% CI 0.97; p=0.02). ConclusionA single dose of tranexamic acid given immediately before surgery reduces blood loss and transfusion rates significantly in advanced ovarian cancer surgery. Tranexamic acid may be recommended as standard prophylactic treatment in advanced ovarian cancer surgery.

  • 25.
    Neider, Daniel
    et al.
    Linköping University, Faculty of Health Sciences. Linköping University, Department of Medicine and Care, Physiology.
    Hallman, Daniel
    Linköping University, Faculty of Health Sciences. Linköping University, Department of Medicine and Care, Physiology.
    Zachrisson, Helene
    Linköping University, Faculty of Health Sciences. Linköping University, Department of Medicine and Care, Clinical Physiology. Östergötlands Läns Landsting, Heart Centre, Department of Clinical Physiology.
    Lindenberger, Marcus
    Linköping University, Faculty of Health Sciences. Linköping University, Department of Medicine and Care, Physiology.
    Länne, Toste
    Linköping University, Faculty of Health Sciences. Linköping University, Department of Medicine and Care, Physiology. Östergötlands Läns Landsting, Heart Centre, Department of Thoracic and Vascular Surgery.
    Venous compliance in the Superficial Femoral Vein and Greater Saphenous Vein in health males.2007In: Kardiovaskulära vårmötet,2007, 2007Conference paper (Other academic)
    Abstract [en]

      

  • 26.
    Nelzén, Oskar
    et al.
    Linköping University, Department of Medical and Health Sciences, Division of Cardiovascular Medicine. Linköping University, Faculty of Medicine and Health Sciences. Region Östergötland, Heart and Medicine Center, Department of Thoracic and Vascular Surgery.
    Skoog, Johan
    Linköping University, Faculty of Medicine and Health Sciences. Linköping University, Department of Medical and Health Sciences, Division of Cardiovascular Medicine.
    Länne, Toste
    Region Östergötland, Heart and Medicine Center, Department of Thoracic and Vascular Surgery. Linköping University, Department of Medical and Health Sciences, Division of Cardiovascular Medicine. Linköping University, Faculty of Medicine and Health Sciences.
    Zachrisson, Helene
    Linköping University, Faculty of Medicine and Health Sciences. Region Östergötland, Heart and Medicine Center, Department of Clinical Physiology in Linköping. Linköping University, Department of Medical and Health Sciences, Division of Cardiovascular Medicine.
    Prediction of Post-interventional Outcome in Great Saphenous Vein Incompetence: The Role of Venous Plethysmography with Selective Superficial Vein Occlusion2016In: European Journal of Vascular and Endovascular Surgery, ISSN 1078-5884, E-ISSN 1532-2165, Vol. 52, no 3, p. 377-384Article in journal (Refereed)
    Abstract [en]

    Objective/Background

    To evaluate whether the outcome of radiofrequency ablation (RFA) treatment of great saphenous vein (GSV) incompetence may be predicted using strain-gauge plethysmography (SGP) with selective occlusion of the superficial venous system.

    Methods

    Seventeen patients (20 limbs) underwent endovenous RFA treatment for GSV incompetence (Clinical Etiology Anatomy Pathophysiology classification C2–C5; “C-group”). Duplex ultrasound (DUS) and SGP were performed with selective occlusion of superficial veins before and after RFA. Selective superficial occlusion was validated, in a control group (C-group) of 12 patients (14 legs), by ascending phlebography. In the RFA group, the time taken to reach 50% and 90% (T50, T90) of maximum venous volume was measured, as well as relative maximal reflux rates (%EV/min). The methodological error and coefficient of variation (CV) were assessed.

    Results

    Nineteen of 20 legs had complete post-operative GSV obliteration using DUS, and refilling times were improved after RFA (T50 11 ± 3 vs. 19 ± 3 s; p < .001; T90 27 ± 5 vs. 47 ± 6 s; p < .001). With SGP, the methodological error and CV for T50 were 4 s and 16%, respectively. Equivalence between pre-operative superficial occlusion and post-operative baseline measurements was achieved in 15 of 17 legs for T50, and 12 of 17 for T90 (three of the 20 legs were excluded due to treatment failure [n = 1], and untreated perforating veins [n = 2]). Mean differences (95% confidence interval) were within the equivalence ranges (T50 1 [–1 to 3] seconds; T90 –3 [–11 to 4] seconds). In the C-group superficial vein occlusion was possible in 12 of 14 legs. The remaining patient (two legs) showed incomplete superficial vein occlusion at ankle level (lipodermatosclerosis) and complete superficial vein occlusion at calf level.

    Conclusion

    SGP with standardized superficial venous occlusion seems to be a reliable method for identifying venous reflux and may be useful in predicting the results of successful RFA treatment.

  • 27.
    Nelzén, Oskar
    et al.
    Linköping University, Department of Medical and Health Sciences, Division of Cardiovascular Medicine. Linköping University, Faculty of Medicine and Health Sciences. Region Östergötland, Heart and Medicine Center, Department of Thoracic and Vascular Surgery.
    Skoog, Johan
    Linköping University, Department of Medical and Health Sciences, Division of Cardiovascular Medicine. Linköping University, Faculty of Medicine and Health Sciences.
    Länne, Toste
    Linköping University, Department of Medical and Health Sciences, Division of Cardiovascular Medicine. Region Östergötland, Heart and Medicine Center, Department of Thoracic and Vascular Surgery. Linköping University, Faculty of Medicine and Health Sciences.
    Zachrisson, Helene
    Linköping University, Department of Medical and Health Sciences, Division of Cardiovascular Medicine. Linköping University, Faculty of Medicine and Health Sciences. Region Östergötland, Heart and Medicine Center, Department of Clinical Physiology in Linköping.
    Residual reflux despite technical successful treatment of Great Saphenous Vein Incompetence?2018In: Charing Cross Venous Workshop strain gauge plethysmography 2018, 2018Conference paper (Other academic)
  • 28.
    Persson, Anders
    et al.
    Linköping University, Faculty of Health Sciences. Linköping University, Department of Medical and Health Sciences, Radiology. Östergötlands Läns Landsting, Centre for Medical Imaging, Department of Radiology UHL. Linköping University, Center for Medical Image Science and Visualization (CMIV).
    Jackowski, Christian
    Linköping University, Center for Medical Image Science and Visualization (CMIV).
    Engström, Elias
    Linköping University, Faculty of Health Sciences. Linköping University, Department of Medical and Health Sciences, Radiology. Linköping University, Center for Medical Image Science and Visualization (CMIV).
    Zachrisson, Helene
    Linköping University, Faculty of Health Sciences. Linköping University, Department of Medical and Health Sciences, Clinical Physiology. Östergötlands Läns Landsting, Heart Centre, Department of Clinical Physiology. Linköping University, Center for Medical Image Science and Visualization (CMIV).
    Advances of dual source, dual-energy imaging in postmortem CT2008In: European Journal of Radiology, ISSN 0720-048X, E-ISSN 1872-7727, Vol. 68, no 3, p. 446-455Article in journal (Refereed)
    Abstract [en]

    This paper focuses on the use of multi-detector row dual-energy computed tomography (DECT) in the evaluation of postmortal examinations. The use of dual energy moves postmortem CT to an entirely new dimension of diagnostic sensitivity where contrast in the image is not merely limited to X-ray attenuation differences, but may include elements of functional and tissue characterization. This additional information may be used to improve the benefit postmortem imaging can provide to supplement and simplify the conventional autopsy. © 2008 Elsevier Ireland Ltd. All rights reserved.

  • 29.
    Skoog, Johan
    et al.
    Linköping University, Faculty of Medicine and Health Sciences. Linköping University, Department of Medical and Health Sciences, Division of Cardiovascular Medicine.
    Lindenberger, Marcus
    Linköping University, Department of Medical and Health Sciences, Division of Cardiovascular Medicine. Linköping University, Faculty of Medicine and Health Sciences. Region Östergötland, Heart and Medicine Center, Department of Cardiology in Linköping.
    Ekman, Mikael
    Ekman Biomed Data, Sweden.
    Holmberg, Bengt
    Linköping University, Department of Medical and Health Sciences. Linköping University, Faculty of Medicine and Health Sciences. Region Östergötland, Heart and Medicine Center, Department of Clinical Physiology in Linköping.
    Zachrisson, Helene
    Linköping University, Department of Medical and Health Sciences, Division of Cardiovascular Medicine. Linköping University, Faculty of Medicine and Health Sciences. Region Östergötland, Heart and Medicine Center, Department of Clinical Physiology in Linköping.
    Länne, Toste
    Linköping University, Department of Medical and Health Sciences, Division of Cardiovascular Medicine. Linköping University, Faculty of Medicine and Health Sciences. Region Östergötland, Heart and Medicine Center, Department of Thoracic and Vascular Surgery.
    Reduced venous compliance: an important determinant for orthostatic intolerance in women with vasovagal syncope2016In: American Journal of Physiology. Regulatory Integrative and Comparative Physiology, ISSN 0363-6119, E-ISSN 1522-1490, Vol. 310, no 3, p. R253-R261Article in journal (Refereed)
    Abstract [en]

    The influence of lower limb venous compliance on orthostatic vasovagal syncope (VVS) is uncertain. The most widespread technique to calculate venous compliance uses a nonphysiological quadratic regression equation. Our aim was therefore to construct a physiologically derived venous wall model (VWM) for calculation of calf venous compliance and to determine the effect of venous compliance on tolerance to maximal lower body negative pressure (LBNP). Venous occlusion plethysmography was used to study calf volume changes in 15 women with VVS (25.5 +/- 1.3 yr of age) and 15 controls (22.8 +/- 0.8 yr of age). The fit of the VWM and the regression equation to the experimentally induced pressure-volume curve was examined. Venous compliance was calculated as the derivative of the modeled pressure-volume relationship. Graded LBNP to presyncope was used to determine the LBNP tolerance index (LTI). The VWM displayed a better fit to the experimentally induced pressure-volume curve (P &lt; 0.0001). Calf blood pooling was similar in the groups and was not correlated to the LTI (r = 0.204, P = 0.30). Venous compliance was significantly reduced at low venous pressures in women with VVS (P = 0.042) and correlated to the LTI (r = 0.459, P = 0.014) in the low pressure range. No correlation was found between venous compliance at high venous pressures and the LTI. In conclusion, the new VWM accurately adopted the curvilinear pressure-volume curve, providing a valid characterization of venous compliance. Reduced venous compliance at low venous pressures may adversely affect mobilization of peripheral venous blood to the central circulation during hypovolemic circulatory stress in women with VVS.

  • 30.
    Skoog, Johan
    et al.
    Linköping University, Department of Medical and Health Sciences, Division of Cardiovascular Medicine. Linköping University, Faculty of Health Sciences. Östergötlands Läns Landsting, Heart and Medicine Center, Department of Clinical Physiology in Linköping.
    Zachrisson, Helene
    Linköping University, Faculty of Health Sciences. Linköping University, Center for Medical Image Science and Visualization (CMIV). Östergötlands Läns Landsting, Heart and Medicine Center, Department of Clinical Physiology in Linköping. Linköping University, Department of Medical and Health Sciences, Division of Cardiovascular Medicine.
    Lindenberger, Marcus
    Linköping University, Department of Medical and Health Sciences, Division of Cardiovascular Medicine. Linköping University, Faculty of Medicine and Health Sciences. Region Östergötland, Heart and Medicine Center, Department of Cardiology in Linköping.
    Ekman, Mikael
    Ekman Biomed Data AB, Gothenburg, Sweden.
    Ewerman, Lea
    Linköping University, Department of Medical and Health Sciences, Division of Cardiovascular Medicine. Linköping University, Faculty of Health Sciences.
    Länne, Toste
    Linköping University, Department of Medical and Health Sciences, Division of Cardiovascular Medicine. Östergötlands Läns Landsting, Heart and Medicine Center, Department of Thoracic and Vascular Surgery. Linköping University, Faculty of Health Sciences.
    Calf venous compliance measured by venous occlusion plethysmography: methodological aspects.2015In: European Journal of Applied Physiology, ISSN 1439-6319, E-ISSN 1439-6327, Vol. 115, no 2, p. 245-56Article in journal (Refereed)
    Abstract [en]

    PURPOSE: Calf venous compliance (C calf) is commonly evaluated with venous occlusion plethysmography (VOP) during a standard cuff deflation protocol. However, the technique relies on two not previously validated assumptions concerning thigh cuff pressure (P cuff) transmission and the impact of net fluid filtration (F filt) on C calf. The aim was to validate VOP in the lower limb and to develop a model to correct for F filt during VOP.

    METHODS: Strain-gauge technique was used to study calf volume changes in 15 women and 10 age-matched men. A thigh cuff was inflated to 60 mmHg for 4 and 8 min with a subsequent decrease of 1 mmHg s(-1). Intravenous pressure (P iv) was measured simultaneously. C calf was determined with the commonly used equation [Compliance = β 1 + 2β 2 × P cuff] describing the pressure-compliance relationship. A model was developed to identify and correct for F filt.

    RESULTS: Transmission of P cuff to P iv was 100 %. The decrease in P cuff correlated well with P iv reduction (r = 0.99, P < 0.001). Overall, our model showed that C calf was underestimated when F filt was not accounted for (all P < 0.01). F filt was higher in women (P < 0.01) and showed a more pronounced effect on C calf compared to men (P < 0.05). The impact of F filt was similar during 4- and 8-min VOP.

    CONCLUSIONS: P cuff is an adequate substitute for P iv in the lower limb. F filt is associated with an underestimation of C calf and differences in the effect of F filt during VOP can be accounted for with the correction model. Thus, our model seems to be a valuable tool in future studies of venous wall function.

  • 31.
    Skoog, Johan
    et al.
    Linköping University, Department of Medical and Health Sciences, Division of Cardiovascular Medicine. Linköping University, Faculty of Medicine and Health Sciences.
    Zachrisson, Helene
    Linköping University, Department of Medical and Health Sciences, Division of Cardiovascular Medicine. Linköping University, Faculty of Medicine and Health Sciences. Region Östergötland, Heart and Medicine Center, Department of Clinical Physiology in Linköping.
    Länne, Toste
    Linköping University, Department of Medical and Health Sciences, Division of Cardiovascular Medicine. Linköping University, Faculty of Medicine and Health Sciences. Region Östergötland, Heart and Medicine Center, Department of Thoracic and Vascular Surgery.
    Lindenberger, Marcus
    Linköping University, Department of Medical and Health Sciences, Division of Cardiovascular Medicine. Linköping University, Faculty of Medicine and Health Sciences. Region Östergötland, Heart and Medicine Center, Department of Cardiology in Linköping.
    Reduced compensatory responses to maintain central blood volume during hypovolemic stress in women with vasovagal syncope2017In: American Journal of Physiology. Regulatory Integrative and Comparative Physiology, ISSN 0363-6119, E-ISSN 1522-1490, Vol. 312, no 1, p. R55-R61Article in journal (Refereed)
    Abstract [en]

    Although vasovagal syncope (VVS) is a common clinical condition, the underlying pathophysiology is not fully understood. A decrease in cardiac output has recently been suggested as a factor in orthostatic VVS. The aim was to investigate compensatory mechanisms to maintain central blood volume and venous return during hypovolemic stress in women with VVS. Fourteen VVS women (25.7 +/- 5.0 yr) and 15 matched controls (22.8 +/- 3.2 yr) were investigated. Single-step and graded lower body negative pressure (LBNP) to presyncope were used to create hypovolemic stress. Peripheral mobilization of venous blood from the arm (capacitance response and net capillary fluid absorption) and lower limb blood pooling (calf capacitance response) were evaluated using a volumetric technique. Cardiovascular responses and plasma norepinephrine (P-NE) were measured. Resting P-NE was elevated in VVS women (P amp;lt; 0.01). Despite a similar hypovolemic stimulus, the increase in P-NE was blunted (P amp;lt; 0.01) and the maximal percent increase in total peripheral resistance was reduced (P amp;lt; 0.05) during graded LBNP in VVS women. The arm capacitance response was slower (P amp;lt; 0.05) and reduced in VVS women at higher levels of LBNP (P amp;lt; 0.05). Capillary fluid absorption from extra-to intravascular space was reduced by similar to 40% in VVS women (P amp;lt; 0.05). Accordingly, the reduction in cardiac output was more pronounced (P amp;lt; 0.05). In conclusion, in VVS women, mobilization of peripheral venous blood and net fluid absorption from tissue to blood during hypovolemic stress were decreased partly as a result of an attenuated vasoconstrictor response. This may seriously impede maintenance of cardiac output during hypovolemic stress and could contribute to the pathogenesis of VVS.

  • 32.
    Skoog, Johan
    et al.
    Linköping University, Faculty of Medicine and Health Sciences. Linköping University, Department of Medical and Health Sciences, Division of Cardiovascular Medicine.
    Zachrisson, Helene
    Linköping University, Department of Medical and Health Sciences, Division of Cardiovascular Medicine. Linköping University, Faculty of Medicine and Health Sciences. Region Östergötland, Heart and Medicine Center, Department of Clinical Physiology in Linköping.
    Länne, Toste
    Linköping University, Department of Medical and Health Sciences, Division of Cardiovascular Medicine. Linköping University, Faculty of Medicine and Health Sciences. Region Östergötland, Heart and Medicine Center, Department of Thoracic and Vascular Surgery.
    Lindenberger, Marcus
    Linköping University, Department of Medical and Health Sciences, Division of Cardiovascular Medicine. Linköping University, Faculty of Medicine and Health Sciences. Region Östergötland, Heart and Medicine Center, Department of Cardiology in Linköping.
    Slower Lower Limb Blood Pooling Increases Orthostatic Tolerance in Women with Vasovagal Syncope2016In: Frontiers in Physiology, ISSN 1664-042X, E-ISSN 1664-042X, Vol. 7, no 232Article in journal (Refereed)
    Abstract [en]

    Background and Aim: Slower lower limb blood pooling and associated blunted sympathetic activation has been detected in healthy women prone to orthostatic syncope. Whether these findings are true also for patients with vasovagal syncope (WS) is unknown. The aim was to investigate initial blood pooling time (pooling(time), time to 50% of total blood pooling) together with hemodynamic responses and orthostatic tolerance during lower body negative pressure (LBNP) in WS and healthy controls. Methods and Results: Fourteen WS women (25.7 +/- 1.3 years) and 15 healthy women (22.8 +/- 0.8 years) were subjected to single-step and graded LBNP to pre-syncope. Lower limb blood pooling (ml 100 ml(-1)), poolingtime (s), hemodynamic responses and LBNP-tolerance were evaluated. LBNP induced comparable lower limb blood pooling in both groups (controls, 3.1 +/- 0.3; WS, 2.9 +/- 0.3 ml 100 ml(-1), P = 0.70). In controls, shorter pooling(time) correlated to higher LBNP-tolerance (r = -0.550, P amp;lt; 0.05) as well as better maintained stroke volume (r =-0.698, P amp;lt; 0.01) and cardiac output (r = -0.563, P amp;lt; 0.05). In contrast, shorter poolingtime correlated to lower LBNP-tolerance in VVS (r = 0.821, P amp;lt; 0.001) and larger decline in stroke volume (r = 0.611, P 0.05). Furthermore, in controls, shorter poolingtime correlated to baroreflex-mediated hemodynamic changes during LBNP, e.g., increased vasoconstriction (P amp;lt; 0.001). In VVS, poolingtime was not correlated with LBNP-induced baroreceptor unloading, but rather highly correlated to resting calf blood flow (P amp;lt; 0.001). Conclusions: Shorter poolingtime seems to elicit greater sympathetic activation with a concomitant higher orthostatic tolerance in healthy women. The contrasting findings in AS indicate a deteriorated vascular sympathetic control suggesting well-defined differences already in the initial responses during orthostatic stress.

  • 33.
    Svensson, C
    et al.
    Region Östergötland, Heart and Medicine Center, Department of Clinical Physiology in Linköping.
    Dremetsika, A
    Eriksson, P
    Zachrisson, Helene
    Linköping University, Department of Medical and Health Sciences, Division of Cardiovascular Medicine. Linköping University, Faculty of Health Sciences. Östergötlands Läns Landsting, Heart and Medicine Center, Department of Clinical Physiology in Linköping. Linköping University, Center for Medical Image Science and Visualization (CMIV).
    Utvidgat undersökningsprotokoll för detektion av tidig arterit2015Conference paper (Refereed)
  • 34.
    Svensson, C
    et al.
    Region Östergötland, Heart and Medicine Center, Department of Clinical Physiology in Linköping.
    Lassvik, C
    Forrssel, C
    Region Östergötland, Heart and Medicine Center, Department of Thoracic and Vascular Surgery.
    Zachrisson, Helene
    Linköping University, Department of Medical and Health Sciences, Division of Cardiovascular Medicine. Linköping University, Faculty of Health Sciences. Östergötlands Läns Landsting, Heart and Medicine Center, Department of Clinical Physiology in Linköping. Linköping University, Center for Medical Image Science and Visualization (CMIV).
    Måltidsprovokation vid bukangina.2015Conference paper (Refereed)
  • 35.
    Svensson, Christina
    et al.
    Linköping University, Department of Medical and Health Sciences, Division of Cardiovascular Medicine. Linköping University, Faculty of Health Sciences. Östergötlands Läns Landsting, Heart and Medicine Center, Department of Clinical Physiology in Linköping.
    Dremetsika, Asimina
    Linköping University, Department of Clinical and Experimental Medicine. Linköping University, Faculty of Health Sciences. Östergötlands Läns Landsting, Heart and Medicine Center, Department of Rheumatology.
    Eriksson, Per
    Linköping University, Department of Clinical and Experimental Medicine. Linköping University, Faculty of Health Sciences. Östergötlands Läns Landsting, Heart and Medicine Center, Department of Rheumatology.
    Zachrisson, Helene
    Linköping University, Department of Medical and Health Sciences, Division of Cardiovascular Medicine. Linköping University, Faculty of Health Sciences. Linköping University, Center for Medical Image Science and Visualization (CMIV). Östergötlands Läns Landsting, Heart and Medicine Center, Department of Clinical Physiology in Linköping.
    High frequency ultrasound för early diagnosis of arteritis2014Conference paper (Other academic)
  • 36.
    Svensson, Christina
    et al.
    Linköping University, Department of Medical and Health Sciences, Division of Cardiovascular Medicine. Linköping University, Faculty of Medicine and Health Sciences.
    Eriksson, Per
    Linköping University, Department of Clinical and Experimental Medicine, Division of Neuro and Inflammation Science. Linköping University, Faculty of Medicine and Health Sciences. Region Östergötland, Heart and Medicine Center, Department of Rheumatology.
    Zachrisson, Helene
    Linköping University, Department of Medical and Health Sciences, Division of Cardiovascular Medicine. Linköping University, Faculty of Medicine and Health Sciences. Region Östergötland, Heart and Medicine Center, Department of Clinical Physiology in Linköping.
    Vascular ultrasound for monitoring of inflammatory activity in Takayasu arteritis2019In: Clinical Physiology and Functional Imaging, ISSN 1475-0961, E-ISSN 1475-097XArticle in journal (Refereed)
    Abstract [en]

    Background Takayasu arteritis (TA) is a rare large-vessel arteritis that primarily affects the aorta and its major branches. The aim of this study was to describe the value of high frequency ultrasound for monitoring of inflammatory activity. Methods Twenty-five patients, range 11-71 years, diagnosed with TA were investigated with duplex ultrasound (DUS) including follow-up studies. Twenty-five healthy controls were also investigated. Nine patients had newly diagnosed active TA. Sixteen patients had stable/inactive disease at baseline DUS, and TA was diagnosed median 4 center dot 5 years previously. Intima-media thickness (IMT), vessel and lumen diameter were measured in the carotid arteries, central neck arteries and the aortic arch. The vessel walls were studied qualitatively. The Takayasu ultrasound index was created for inflammatory activity scoring. Results Intima-media thickness in common carotid artery (CCA) was (median and 25-75 percentile parenthetic) 2 center dot 3 mm (1 center dot 7-2 center dot 9) in clinically active TA, 1 center dot 2 mm (1 center dot 1-1 center dot 6) in clinically stable TA (Pamp;lt;0 center dot 001) and 0 center dot 5 mm (0 center dot 5-0 center dot 6) in healthy controls (Pamp;lt;0 center dot 001). Clinically active TA had prominent increase in IMT and/or increased vessel diameter, and/or intramural arteries, and/or hypoechogenic areas interpreted as oedema in the vessel wall. TA in clinical remission was characterized by increased IMT with medium to high echogenicity with or without fibrotic stripes. The Takayasu ultrasound index was higher in patients with active disease versus treated disease, 2 center dot 55 (1 center dot 60-3 center dot 05) versus 1 center dot 30 (1 center dot 00-1 center dot 58), (P = 0 center dot 003). Conclusion DUS is an excellent tool to monitor inflammatory changes in the vessel wall in TA. Further DUS studies in larger patient populations are warranted.

  • 37.
    Svensson, Christine
    et al.
    Linköping University, Department of Medical and Health Sciences, Division of Cardiovascular Medicine. Linköping University, Faculty of Medicine and Health Sciences. Region Östergötland, Heart and Medicine Center, Department of Clinical Physiology in Linköping.
    Lassvik, C
    Linköping University, Department of Medical and Health Sciences, Division of Cardiovascular Medicine. Linköping University, Faculty of Medicine and Health Sciences. Region Östergötland, Heart and Medicine Center, Department of Clinical Physiology in Linköping.
    Zachrisson, Helene
    Linköping University, Department of Medical and Health Sciences, Division of Cardiovascular Medicine. Linköping University, Faculty of Medicine and Health Sciences. Region Östergötland, Heart and Medicine Center, Department of Clinical Physiology in Linköping.
    Nutcracker Syndrome, vascular imaging with ultrasound2018In: Cardiovasc Pharm Open Access, ISSN 2329-6607, Vol. 7, no 2, article id 1000235Article in journal (Refereed)
    Abstract [en]

    Nutcracker Syndrome (NCS) or Left Renal Vein (LRV) entrapment is rare and may be caused by compression of the vein between the aorta and the Superior Mesenteric Artery (SMA). LRV hypertension may lead to varicosities. The syndrome is characterized by a complex of symptoms with substantial variations, the diagnosis is difficult and therefor often delayed. The diagnosis may be settled by many imaging methods, such as renal angiography, retrograde phlebography, Computed Tomography (CT), Magnetic Resonance Imaging (MRI) and Doppler Ultrasonography (DUS). The degree of stenosis may be detected measuring Doppler flow velocities by DUS.

    A 50-year old female with Crohn´s disease treated by ileocecal resection, performed 20 years ago, and symptomatic epilepsy treated by a vagal stimulator, had newly added symptoms of abdominal pain, weight loss, dizziness, irregular bowel movements, and increasing fatigue. Blood parameters and physical examination were normal. CT showed no signs of active Crohn´s disease. The left renal veins and the left ovarian vein were dilated and the aorto-mesenteric angle was only 22 degrees.

    DUS (Siemens S2000, 6 and 9 MHz transducers) performed one month later confirmed the findings of the CT with typical findings of NCS. DUS will play a crucial role in Nutcracker syndrome considering flow velocity, diameter measurement, anatomy and aorto-mesenteric angle. DUS is a non-invasive, cheap modality that gives a very good resolution that can define vessel walls and evaluate flow velocity conditions. This patient had mild symptoms that led to a conservative treatment whereas epilepsy and Crohn ́s disease was the main problem. If severe symptoms occur different kinds of treatments are available, such as stenting of LRV, open surgical interventions, ablation of collateral pelvic veins and coil embolization.

  • 38.
    Zachrisson, Helene
    Linköping University, Department of Medical and Health Sciences, Division of Cardiovascular Medicine. Linköping University, Faculty of Medicine and Health Sciences. Linköping University, Center for Medical Image Science and Visualization (CMIV). Region Östergötland, Heart and Medicine Center, Department of Clinical Physiology in Linköping.
    Biomedicinska analytiker är nyckelspelare2018In: Dagens medicin, ISSN 1104-7488Article in journal (Other academic)
    Abstract [sv]

    Snabbspår med ultraljudsundersökning är långt ifrån standard, trots att metoden visat sig vara viktig för att snabbt ställa diagnosen jättecellsarterit. I Linköping har man redan infört en fungerande modell.

  • 39.
    Zachrisson, Helene
    Linköping University, Faculty of Health Sciences. Linköping University, Department of Medicine and Care, Clinical Physiology. Östergötlands Läns Landsting, Heart Centre, Department of Clinical Physiology.
    Carotisstenos, logistik. Vilka opereras och när.2007In: Svenska Neurologmötet,2007, 2007Conference paper (Other academic)
  • 40.
    Zachrisson, Helene
    Linköping University, Faculty of Health Sciences. Linköping University, Department of Medicine and Care, Clinical Physiology. Östergötlands Läns Landsting, Heart Centre, Department of Clinical Physiology.
    Duplexundersökning med måltidsprovokation vid bukangina2006In: Kardiovaskulära vårmöte,2006, 2006Conference paper (Other academic)
  • 41.
    Zachrisson, Helene
    Department of Clinical Physiology, University of Gothenburg, Sweden.
    Noninvasive assessment of cerebral circulation before, during and after carotid surgery2000Doctoral thesis, monograph (Other academic)
    Abstract [en]

    Non-invasive ultrasound investigations were evaluated in patients with carotid artery stenosis in comparison with radiological disease gradations and perioperative blood pressure measurements. The aim was to assess cerebrovascular hemodynamics before, during and after carotid thrombendarterectomy (CEA) in relation to the clinical outcome of the surgical intervention.Intracranial collateral blood flow as a consequence of high grade carotid artery disease can be investigated by means of blood flow velocity measurements with 3D-transcranial Doppler flow mapping and proximal common carotid artery compressions. The value and risks of common carotid artery compression were therefore assessed. No adverse effects were seen in 3383 patient studies retrospectively reviewed. In addition, we found that transcranial Doppler without carotid compression may lead to false identification of the posterior cerebral artery.Preoperative blood flow velocities within the carotid stenosis and poststenotic blood pressures during intraoperative carotid clamping were analysed with respect to some serious postoperative complications. We found that blood flow velocities within severe internal carotid artery (ICA) stenoses are inversely related to the poststenotic collateral blood pressure. High diastolic blood flow velocities within the ICA stenosis might indicate low collateral blood pressures and increased risk for severe postoperative neurological complications. The discrepancies occasionally seen between preoperative ultrasound investigation and angiography might therefore be explained by high collateral backpressures, which may induce unusually low blood flow velocities within severe ICA diameter reductions.The carotid compression test, performed during the preoperative transcranial Doppler investigation, was used to predict middle cerebral artery (MCA) blood flow reductions during intraoperative carotid artery cross-clamping. Surprisingly, we found a greater decrease of the MCA blood flow velocities during the carotid compression test compared with the flow changes during cross-clamping. Signs of cerebrovascular autoregulation due to carotid compression were not reproducible during carotid clamping under general anaesthesia. The few patients with postoperative adverse reactions happened to show a pattern of low collateral blood pressures and relatively high MCA blood flow velocities during cross-clamping. Since general anaesthesia affects cerebral autoregulation we performed a postoperative transcranial Doppler study to assess the MCA blood flow pattern after surgical restoration of normal ICA blood flow. In the majority of the patients, we observed increased blood flow velocities bilaterally within the MCA, which might be a result of postoperative hyperperfusion or autonomic imbalance of carotid sinus baroreceptors.In conclusion, evaluations of cerebrovascular hemodynamics in CEA patients might give important information indicating risks of complications.

  • 42.
    Zachrisson, Helene
    Linköping University, Department of Medical and Health Sciences, Clinical Physiology. Linköping University, Faculty of Health Sciences. Linköping University, Center for Medical Image Science and Visualization (CMIV). Östergötlands Läns Landsting, Heart and Medicine Center, Department of Clinical Physiology in Linköping.
    Transkraniell doppler/duplex2002In: Klinisk fysiologisk kärldiagnostik / [ed] Tomas Jogestrand och Stefan Rosfors, Lund: Studentlitteratur AB, 2002, p. 212-221Chapter in book (Other academic)
  • 43.
    Zachrisson, Helene
    et al.
    Linköping University, Department of Medical and Health Sciences, Clinical Physiology. Linköping University, Faculty of Health Sciences. Linköping University, Center for Medical Image Science and Visualization (CMIV). Östergötlands Läns Landsting, Heart and Medicine Center, Department of Clinical Physiology in Linköping.
    Berthelsen, B
    Blomstrand, C
    Holm, J
    Volkmann, R
    Influence of poststenotic collateral pressure on blood flow velocities within high-grade carotid artery stenosis: differences between morphologic and functional measurements.2001In: Journal of Vascular Surgery, ISSN 0741-5214, E-ISSN 1097-6809, Vol. 34, no 2, p. 263-8Article in journal (Refereed)
    Abstract [en]

    PURPOSE: The driving force for blood flow through a high-grade stenosis in the internal carotid artery can be expressed as the pressure gradient over the stenosis itself, which, however, might be reduced by the back pressure exerted by distal collateral vessels. Theoretically the maximum blood flow velocity as a measure of the functional grade of obstruction may therefore be lower than what is expected from morphologic gradations of the stenosis. This study was designed to test prospectively the influence of intracranial collateral vessels on blood flow velocities within high-grade internal carotid artery stenoses.

    PATIENTS AND METHODS: Forty-five consecutive patients (age 66 +/- 11) with high-grade internal carotid artery stenoses were investigated before and during carotid endarterectomy. The preoperative investigations included duplex ultrasound scanning of the neck vessels, transcranial Doppler scanning for assessment of collateral flow to the middle cerebral artery and angiography. Carotid endarterectomy was performed with patients under deep general anesthesia without a shunt. Systolic and diastolic internal carotid artery blood pressures were measured before and during intraoperative cross-clamping (ie, stump pressure) of the carotid arteries.

    RESULTS: Within high-grade internal carotid artery stenoses, maximum systolic and end-diastolic blood flow velocities showed a significant inverse correlation to the corresponding systolic and diastolic stump blood internal carotid artery blood pressures. All patients with spontaneous collateral flow to the ipsilateral anterior part of the circle of Willis were divided into a group with relatively high and another one with low end-diastolic blood flow velocities. The stump pressure was significantly lower in patients with high end-diastolic blood flow velocities in spite of the fact that the mean angiographic grade of stenosis did not differ significantly between the groups.

    CONCLUSIONS: Flow velocities within a high-grade internal carotid artery stenosis are inversely dependent on the stump pressure, that is the poststenotic collateral perfusion pressure. This should be taken into consideration in case of discrepancies between angiography and ultrasound outcome.

  • 44.
    Zachrisson, Helene
    et al.
    Linköping University, Department of Medical and Health Sciences, Clinical Physiology. Linköping University, Faculty of Health Sciences. Linköping University, Center for Medical Image Science and Visualization (CMIV). Östergötlands Läns Landsting, Heart and Medicine Center, Department of Clinical Physiology in Linköping.
    Berthelsen, Brigitte
    Blomstrand, Christian
    Holm, Jan
    Kjällman, Lena
    Volkmann, Reinhard
    High diastolic flow velocities in severe internal carotid artery stenosis: a sign of increased surgical risk?2000In: Journal of Vascular Surgery, ISSN 0741-5214, E-ISSN 1097-6809, Vol. 31, no 3, p. 477-83Article in journal (Refereed)
    Abstract [en]

    PURPOSE: We reviewed the history and preoperative investigations of patients with early postoperative neurologic events after carotid thromboendarterectomy in an attempt to identify risk factors for neurologic complications.

    METHODS: Patients with neurologic events/complications (S group, n = 14 patients) were compared with an age- and disease-matched control group (C group, n = 42 patients) selected from the whole carotid thromboendarterectomy material between 1987 and 1996. In this retrospective study, we re-evaluated the maximum systolic and end diastolic flow velocities within the internal carotid artery (ICA) using video recordings of preoperative Duplex ultrasound scan investigations. The flow velocity variables were compared with preoperative carotid angiography and intraoperative ICA stump pressure measurement.

    RESULTS: S-group did not differ from C-group concerning either cardiovascular risk factors or diseases, ipsilateral and contralateral angiographic grade of ICA stenosis, or history of cerebral infarctions. Nevertheless, in contrast to control subjects, patients with early postoperative major stroke had higher end diastolic flow velocities and lower ICA stump pressures. Patients with postoperative minor stroke, transient ischemic attack, or amaurosis fugax did not differ significantly from the control subjects. Among patients with ICA stenosis of 75% or more, end diastolic flow velocities were correlated to the diastolic stump pressures.

    CONCLUSION: Diastolic flow velocities within severe internal carotid artery stenosis are dependent on the level of the collateral perfusion pressure distally to the stenosis (ie, high values indicate a low internal carotid artery stump pressure), which seems to be a risk factor for early postoperative strokes.

  • 45.
    Zachrisson, Helene
    et al.
    Linköping University, Department of Medical and Health Sciences, Clinical Physiology. Linköping University, Faculty of Health Sciences. Linköping University, Center for Medical Image Science and Visualization (CMIV). Östergötlands Läns Landsting, Heart and Medicine Center, Department of Clinical Physiology in Linköping.
    Blomstrand, C
    Holm, J
    Mattsson, E
    Volkmann, R
    Changes in middle cerebral artery blood flow after carotid endarterectomy as monitored by transcranial Doppler.2002In: Journal of Vascular Surgery, ISSN 0741-5214, E-ISSN 1097-6809, Vol. 36, no 2, p. 285-90Article in journal (Refereed)
    Abstract [en]

    OBJECTIVE: By using transcranial Doppler (TCD) it is possible to measure blood flow velocities within the circle of Willis. In this study, TCD was performed before and after carotid endarterectomy (CEA) with the aim to describe cerebral hemodynamics after normalization of the carotid artery blood flow.

    METHODS: Thirty CEA patients were consecutively entered into the TCD study, whereas 15 patients were referred for postoperative TCD for various clinical reasons. All 45 patients were investigated by using TCD: first preoperatively, then during the first few days after CEA before discharge from the hospital, and finally 3 to 12 months later. In addition, all patients underwent duplex investigation of the internal carotid artery the day before surgery and 3 months postoperatively. For the analysis, the patients were divided into two groups, one with (S-group), suspected postoperative neurologic complications/symptoms and another one without (C-group). Six patients were assigned to the S-group and 37 to the C-group, the latter including two patients who underwent bilateral CEAs.

    RESULTS: In the whole study group,a significant postoperative increase in systolic flow velocity was recorded bilaterally in the middle cerebral artery (MCA) as measured some days after surgery. The patients in the S-group showed high blood flow velocities mainly in the MCA on the ipsilateral side. A contralateral flow velocity increase did not occur in patients with very severe contralateral stenosis or occlusion (n = 9) if the late follow-up investigation was chosen as a reference value. Twenty patients in the C-group formed a subgroup with high blood pressure and/or headache postoperatively (CB-group) The other 19 patients were referred to as the CA-group. The CB- and S-groups showed more pronounced vessel disease in internal carotid artery on the contralateral side combined with lower collateral capacity in the circle of Willis compared to the CA-group. In the S-group the mean +/- standard deviation peak systolic velocity in ipsilateral MCA increased from a preoperative value of 0.71 +/- 0.22 m/sec to 2.23 +/- 0.72 m/sec (P <.005). In the CB-group, we observed a bilateral MCA blood flow velocity increase from 0.72 +/- 0.18 to 1.35 +/- 0.56 m/sec (P <.0001) on the ipsilateral side and from 0.82 +/- 0.37 to 1.28 +/- 0.66 m/sec (P < 0.001) on the contralateral side. In the CA-group, we observed minor bilateral blood flow velocity increases in the MCA, from 0.79 +/- 0.25 m/sec to 1.03 +/- 0.33 m/sec on the ipsilateral (P <.001) and from 0.70 +/- 0.17 m/sec to 0.93 +/- 0.26 m/sec on the contralateral side (P <.005). At the follow-up 3 to 12 months after surgery, the MCA flow velocities had returned to normal.

    CONCLUSIONS: Soon after surgery, blood flow velocity increases often bilaterally in the MCA. However a contralateral flow velocity increase did not occur in patients with very severe contralateral stenosis or occlusion if the late follow-up investigation was chosen as a reference value. The clinical significance of bilateral flow velocity increases is uncertain, but very high blood flow velocities might be a signal for cerebrovascular hyperperfusion. In those patients, increased postoperative surveillance is recommended.

  • 46.
    Zachrisson, Helene
    et al.
    Linköping University, Center for Medical Image Science and Visualization, CMIV. Linköping University, Department of Medicine and Health Sciences, Clinical Physiology . Linköping University, Faculty of Health Sciences.
    Engström, E
    Linköping University, Department of Medicine and Health Sciences, Clinical Physiology . Linköping University, Faculty of Health Sciences.
    Engvall, Jan
    Linköping University, Center for Medical Image Science and Visualization, CMIV. Linköping University, Department of Medicine and Health Sciences, Clinical Physiology . Linköping University, Faculty of Health Sciences.
    Wigström, Lars
    Linköping University, Center for Medical Image Science and Visualization, CMIV. Linköping University, Department of Medicine and Health Sciences, Clinical Physiology . Linköping University, Faculty of Health Sciences.
    Smedby, Örjan
    Linköping University, Center for Medical Image Science and Visualization, CMIV. Linköping University, Department of Medicine and Health Sciences, Radiology . Linköping University, Faculty of Health Sciences.
    Persson, Anders
    Linköping University, Center for Medical Image Science and Visualization, CMIV. Linköping University, Department of Medicine and Health Sciences, Radiology . Linköping University, Faculty of Health Sciences.
    Soft tissue discrimination ex vivo by dual energy computed tomography2010In: European Journal of Radiology, ISSN 0720-048X, E-ISSN 1872-7727, Vol. 75, no 2, p. E124-E128Article in journal (Refereed)
    Abstract [en]

    PURPOSE: Dual Energy Computed Tomography (DECT) may provide additional information about the chemical composition of tissues compared to examination with a single X-ray energy. The aim of this in vitro study was to test whether combining two energies may significantly improve the detection of soft tissue components commonly present in arterial plaques. METHODS: Tissue samples of myocardial and psoas muscle, venous and arterial thrombus as well as fat from different locations were scanned using a SOMATOM Definition Dual Source CT system (Siemens AG, Medical Solutions, Forchheim, Germany) with simultaneous tube voltages of 140 and 80kV. The attenuation (Hounsfield units, HU) at 80 and 140kV was measured in representative regions of interest, and the association between measured HU values and tissue types was tested with logistic regression. RESULTS: The combination of two energy levels (80 and 140kV) significantly improved (p<0.001) the ability to correctly classify venous thrombus vs arterial thrombus, myocardium or psoas; arterial thrombus vs myocardium or psoas; myocardium vs psoas; as well as the differentiation between fat tissue from various locations. Single energy alone was sufficient for distinguishing fat from other tissues. CONCLUSION: DECT offers significantly improved in vitro differentiation between soft tissues occurring in plaques. If this corresponds to better tissue discrimination in vivo needs to be clarified in future studies.

  • 47.
    Zachrisson, Helene
    et al.
    Linköping University, Department of Medical and Health Sciences, Clinical Physiology. Linköping University, Faculty of Health Sciences. Östergötlands Läns Landsting, Heart and Medicine Centre, Department of Clinical Physiology UHL.
    Fouladiun, Marita
    Sahlgrens Academy.
    Blomstrand, Christian
    Sahlgrens Academy.
    Volkmann, Reinhard
    Sahlgrens Academy.
    Functional assessment of high-grade ICA stenosis with duplex ultrasound and transcranial Doppler2012In: Clinical Physiology and Functional Imaging, ISSN 1475-0961, E-ISSN 1475-097X, Vol. 32, no 3, p. 241-246Article in journal (Refereed)
    Abstract [en]

    Background: Duplex ultrasound (DUS) has shown a andgt;90% accuracy compared to angiography, concerning the degree of internal carotid artery (ICA) stenosis. However, uncertainty may occur in a severe stenosis, in which peak systolic velocity (PSV) may decrease owing to high flow resistance or high backward pressure. We investigated intracranial collateral flows using transcranial Doppler (TCD) to further evaluate the hemodynamic significance of high-grade ICA stenosis. Methods: In this retrospective study, 320 consecutive symptomatic patients were examined. The degree of ICA stenosis and collateral capacity in the circle of Willis was investigated by DUS and TCD. In addition, magnetic resonance angiography (MRA) was added in a subgroup of 204 patients. The criterion for hemodynamic significant ICA stenosis was established collateral flow. Results: In 91% of all symptomatic vessels (291 vessels), an ICA stenosis of 70% was found. Established collateral flow always indicated precerebral carotid artery disease of 70%. Furthermore, in 11% of the whole study material, collateral reserve capacity was found despite high-grade (70%) ICA stenosis. PSV in ICA andlt; 2 5 m s) 1 was combined with established collateral flow and MRA stenosis of 70% in 9% (19 arterial systems). In 4%, doubt existed concerning the degree of stenosis after DUS. Conclusion: Transcranial Doppler helps to determine whether an ICA stenosis is of hemodynamic significance and to assess collateral patterns. Established collateral blood flow will help to identify patients with 70% (ECST) carotid artery disease. TCD might be of value when flow velocity criteria combined with plaque assessment by DUS are inclusive. Other diagnostic methods may also be considered.

  • 48.
    Zachrisson, Helene
    et al.
    Linköping University, Department of Medical and Health Sciences, Clinical Physiology. Linköping University, Faculty of Health Sciences. Linköping University, Center for Medical Image Science and Visualization (CMIV). Östergötlands Läns Landsting, Heart and Medicine Center, Department of Clinical Physiology in Linköping.
    Jatuzis, D
    Blomstrand, C
    Holm, J
    Volkmann, R
    Middle cerebral artery circulation during carotid surgery. A transcranial Doppler study.2000In: Scandinavian Cardiovascular Journal, ISSN 1401-7431, E-ISSN 1651-2006, Vol. 34, no 6, p. 597-602Article in journal (Refereed)
    Abstract [en]

    OBJECTIVE: Perioperative carotid cross-clamping might induce low stump pressures as well as hypoperfusion of the middle cerebral artery. In this study blood flow velocities in the middle cerebral artery were compared with intraoperative measurements of the poststenotic carotid blood pressure.

    DESIGN: Forty-one patients with internal carotid artery stenosis were operated on without shunting, under general anesthesia. Poststenotic carotid pressures and middle cerebral artery flow velocities were measured before and during cross-clamping. The hemodynamic responses to preoperative carotid compressions and intraoperative cross-clamping were evaluated.

    RESULTS: In seven patients the poststenotic carotid blood pressure decreased on clamping despite unchanged or even increased middle cerebral artery blood flow velocities. In all other patients, pressure changes were significantly correlated to the decrease in middle cerebral artery blood flow velocities. Autoregulatory blood flow velocity responses after preoperative common carotid artery compression were not reproducible by cross-clamping.

    CONCLUSIONS: Stump blood pressure measurements may not reflect middle cerebral artery perfusion in about 20% of thrombendarterectomies performed under general anesthesia. A possible explanation might be dimished cerebral autoregulation and changes in collateral flow distributions.

  • 49.
    Zachrisson, Helene
    et al.
    Linköping University, Department of Medical and Health Sciences, Clinical Physiology. Linköping University, Faculty of Health Sciences. Östergötlands Läns Landsting, Heart and Medicine Centre, Department of Clinical Physiology UHL.
    Lindenberger, Marcus
    Linköping University, Department of Medical and Health Sciences, Physiology. Linköping University, Faculty of Health Sciences.
    Hallman, Daniel
    Linköping University, Department of Medical and Health Sciences, Physiology. Linköping University, Faculty of Health Sciences.
    Ekman, M.
    Biomed Data AB, Gothenburg, Sweden.
    Neider, Daniel
    Linköping University, Department of Medical and Health Sciences, Physiology. Linköping University, Faculty of Health Sciences.
    Länne, Toste
    Linköping University, Department of Medical and Health Sciences, Physiology. Linköping University, Faculty of Health Sciences. Östergötlands Läns Landsting, Heart and Medicine Centre, Department of Thoracic and Vascular Surgery in Östergötland.
    Diameter and compliance of the greater saphenous vein - effect of age and nitroglycerine2011In: Clinical Physiology and Functional Imaging, ISSN 1475-0961, E-ISSN 1475-097X, Vol. 31, no 4, p. 300-306Article in journal (Refereed)
    Abstract [en]

    Objectives: The greater saphenous vein (GSV) is commonly used in autologous vein graft surgery. GSV diameter has proven to influence graft patency, and furthermore venous compliance might be of importance. The purpose of the study was to evaluate the effect of age on GSV diameter and compliance, and to evaluate the effect of nitroglycerine (NTG). Methods: The diameter and compliance of the GSV, with and without NTG, were examined with B-mode ultrasound in 12 elderly (70.3 +/- 1.2 year) and 15 young (25.1 +/- 0.6 year) men. The GSV diameter at the thigh and calf level was measured at rest, after 6 min of venous stasis (60 mmHg) and after NTG administration. Pressure-area curves during a linear venous pressure decrease were produced. Venous compliance was calculated using the quadratic regression equation (area) = beta(0) + beta(1) (cuff pressure) + beta(2) (cuff pressure)(2). Results: GVS diameter between the groups showed significant lower diameter in elderly compared to young men (Pless than0.05). Venous occlusion increased GSV diameter in elderly men (Pless than0.01) as well as young men (Pless than0.001). NTG increased GSV diameter in elderly men (Pless than0.01) with an equal trend in young men. During venous occlusion, after administration of NTG, GSV diameter increased further in both elderly (Pless than0.01) and young men (Pless than0.001). GSV compliance was decreased in elderly (beta(1), 0.037 +/- 0019, beta(2), -0.000064 +/- 00017) versus young men (beta(1), 0.128 +/- 0.013, beta(2), -0.00010 +/- 000018) [Pless than0.001 (beta(1)), Pless than0.02 (beta(2))]. Conclusions: Baseline GSV diameter as well as GSV compliance is decreased in elderly men compared to the young subjects. As reduced GSV diameter as well as reduced compliance is related to decreased graft patency, these findings might be of importance for the uses of GSV as graft material in cardiovascular bypass surgery. The clinical value has to be clarified in future studies.

  • 50.
    Zachrisson, Helene
    et al.
    Linköping University, Faculty of Health Sciences. Linköping University, Department of Medicine and Health Sciences, Clinical Physiology . Östergötlands Läns Landsting, Heart Centre, Department of Clinical Physiology.
    Lindenberger, Marcus
    Linköping University, Faculty of Health Sciences. Linköping University, Department of Medicine and Health Sciences, Physiology .
    Hallman, Daniel
    Linköping University, Faculty of Health Sciences. Linköping University, Department of Medicine and Health Sciences.
    Länne, Toste
    Linköping University, Faculty of Health Sciences. Linköping University, Department of Medicine and Health Sciences, Physiology . Östergötlands Läns Landsting, Heart Centre, Department of Thoracic and Vascular Surgery.
    Diameter and compliance of the great saphenous vein2008In: Experimental Biology,2008, 2008Conference paper (Refereed)
12 1 - 50 of 58
CiteExportLink to result list
Permanent link
Cite
Citation style
  • apa
  • harvard1
  • ieee
  • modern-language-association-8th-edition
  • vancouver
  • oxford
  • Other style
More styles
Language
  • de-DE
  • en-GB
  • en-US
  • fi-FI
  • nn-NO
  • nn-NB
  • sv-SE
  • Other locale
More languages
Output format
  • html
  • text
  • asciidoc
  • rtf